Interstate 495 (Capital Beltway)

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Interstate 495
Auxiliary route of the Interstate Highway System

Length:

64 mi (103 km)

Formed:

1958

Beltway around Washington, DC

Major
junctions:

I-295 near Forest Heights, MD

US 50 (I-595) near Glenarden, MD

MD 295 (Balt./Wash. Parkway) near Greenbelt, MD

I-95 near College Park, MD

I-270 near Bethesda, MD

SR 267 near Tysons Corner, VA

I-66 near Falls Church, VA

I-95/I-395 near Springfield, VA

Interstate 495 (abbreviated I-495) is a freeway-class interstate highway which circles Washington, D.C. and its inner suburbs in Maryland and Virginia. I-495 is widely known as the Capital Beltway or simply as the Beltway, especially when the context of Washington, D.C., is clear. It is the basis of the phrase "inside the Beltway", used when referring to issues dealing with American government and politics. Interstate 95 utilizes the southern and eastern half of the Capital Beltway to circumnavigate Washington, D.C., and is cosigned with Interstate 495 along that route.

[edit] Counties traversed

[edit] Maryland

[edit] Virginia

[edit] Major cities

[edit] Maryland

[edit] Virginia

[edit] Route description

Because of the presence of I-95, I-495 technically begins at the College Park Interchange near College Park, Maryland and technically ends at the Springfield Interchange in Springfield, Virginia. However, because the signage of I-495 is continuous, and because the zero milepost of I-495 is concurrent with I-95's zero milepost at the northern end of the Woodrow Wilson Memorial Bridge in Maryland, the route is generally judged to begin there.

[edit] I-95/I-495 Multiplex in Maryland

The two routes, eight lanes wide, travel together over the Woodrow Wilson Bridge and touch down in Prince George's County west of Forest Heights. I-95/I-495 immediately encounter the southern terminus of Interstate 295, known as the Anacostia Freeway, a route that serves downtown Washington D.C. and connects to the planned alignment of I-95 through D.C., Interstate 395. Passing through the interchange, currently under major reconstruction as part of the bridge replacement project, the two routes interchange with MD 210, a major north-south route into southern D.C. Beyond the MD 210 interchange (also under construction) the Beltway exits the eastern edge of the bridge replacement project.

The two Interstates continue along the Capital Beltway, interchanging with various local highways such as MD 5 and MD 4 on either side of Andrews Air Force Base, which the Beltway travels very close to near its northern edge. Turning north past the MD 4 interchange, the Beltway runs through Glenarden, interchanging with MD 202, US 50, and MD 450, the latter route offering access to the New Carrollton metro station and the New Carrollton metropolitan area.

Turning northwest the Beltway enters Greenbelt Park, intersecting the Baltimore-Washington Parkway in the northeastern edge of the park. Just after the B-W Parkway, the two routes interchange with MD 201, which connects to the southern terminus of the B-W Parkway at US 50 near the D.C. line. Now turned fully west, the Beltway runs through the northern edge of College Park, interchanging with the Greenbelt metro station's access roadway and US 1.

Beyond the US 1 interchange, Interstate 95 encounters its own route at the College Park Interchange and separates from Interstate 495 within this interchange. I-495 continues west, alone, on the Capital Beltway, while I-95 turns north onto its own planned alignment. The interchange includes access to a Park and Ride.

[edit] I-495 in Maryland

Continuing west from the College Park Interchange, I-495 enters a heavily developed and populated area. Passing underneath MD 212 with no interchange, the route interchanges with MD 650 near the George Washington Cemetery. After bisecting the Northwest Branch Park, the Beltway interchanges with MD 193 and US 29 south of Four Corners; the interchanges are little more than half a mile apart. Southbound US 29 is the main route into downtown Silver Spring.

Squeezing past Argyle Park and Sligo Creek Golf Course, the Beltway interchanges with MD 97 northwest of Silver Spring and follows an alignment formerly known as Rock Creek Parkway. Twisting along the alignment, through and around Rock Creek Park, the route interchanges with MD 185 near the National Naval Medical Center. Turning northwest, I-495 soon encounters the southern terminus of Interstate 270.

I-270 and I-495 split at a highly complex wye junction, with separate HOV connections to I-270's HOV lanes and separate ramps to and from MD 355 (formerly known as US 240). The old Rock Creek Parkway alignment follows I-270 north, while I-495 turns west and enters the only other six-lane segment of the Beltway still in existence; significant levels of traffic exit onto I-270 north, leaving the six-lane segment west of the split adequate.

Interchanging with MD 187, I-495 soon meets Interstate 270 Spur, the other side of the I-270/I-495 triangle. I-495 joins I-270 Spur at a converging wye junction; Inner Loop traffic exits from itself at the southern terminus of I-270 Spur, while Outer Loop traffic crosses the spur and enters it from the right. The two carriageways of I-495 temporarily widen to ten lanes and remain ten lanes as far as the MD 190 and Cabin John Parkway interchanges, where the route narrows to eight lanes again. Turning sharply to the west, I-495 meets the Clara Barton Parkway just to the north of the Potomac River, and soon crosses into Virginia over the American Legion Memorial Bridge.

[edit] I-495 in Virginia

Immediately after crossing into Virginia, I-495 encounters the western terminus of the George Washington Memorial Parkway at a trumpet interchange. Continuing south the Beltway interchanges with VA 193 south of Dranesville District Park, then reaches the massive triangle of interchanges between itself, the Dulles Airport Access Road, VA 267, and VA 123. The former interchange with the toll road is a directional interchange, while the latter is a cloverleaf; the entire complex occurs east of Tysons Corner, near the massive Tysons Corner Center shopping mall.

Now running south, the Beltway interchanges with VA 7, the Leesburg Pike, east of the shopping center; passing Dunn Loring to the east the route soon reaches the complex interchange with Interstate 66. In a similar setup as the I-270/I-495 interchange, dedicated HOV connections exist between I-495 and I-66, with many reversible and other directional ramps providing the remaining connections. Curiously, there is no access between the Outer Loop and I-66 east; also, there are multiple ramps from I-66 east to the Inner Loop, with one ramp exiting from the left side of I-66 east and the other exiting from the right.

South of the I-66 interchange, the Beltway crosses under US 29 and VA 237 with no access, then encounters a large braided interchange between itself, US 50, and two local roads; the direct interchange between I-495 and US 50 is a full cloverleaf, while the braided local interchanges between I-495, US 50 and the local roads are modified SPUIs. The entire complex is bounded on the northeast side by Fairview Lake and on the southwest side by an office complex occupied by Mobil.

Continuing due south, the route interchanges with Gallows Road south of the Mobil offices, then skirts the eastern edge of Mill Creek Park before interchanging with VA 236 southwest of Annandale Community Park. Running along the eastern edge of Wakefield Park the Beltway turns southeast and interchanges with the nearly straight VA 620 before turning east near Flag Run Park and running into Springfield, meeting the Springfield Interchange southeast of the Shirley Industrial Complex.

[edit] I-95/I-495 Multiplex in Virginia

Here, I-495 technically ends as mentioned above, and I-95 joins the Beltway within the massive interchange, currently under reconstruction to cater for the many and varied traffic flows. I-495 also meets the southern terminus of Interstate 395 within the massive interchange complex.

Running due east away from the interchange, crossing to the south of Backlick Stream Valley Park, the two routes interchange with VA 613 a mile east of the Springfield Interchange. Continuing east, the Beltway encounters a diamond interchange with a connector road linking to Eisenhower Avenue, which parallels the Beltway for a short distance. Skirting the northern edges of Loftridge Park and Burgundy Park the two routes enter Alexandria and soon reach VA 241, a direct route into the city. Within the interchange, the Beltway enters the western edge of the Woodrow Wilson Memorial Bridge replacement project.

Continuing east within the project limits, the two routes encounter US 1, whose interchange with the Beltway is also undergoing major reconstruction as part of the bridge replacement project. Finally, beyond the interchange, I-95 and I-495 cross Jones Point Park and exit Virginia via the Woodrow Wilson Bridge.

[edit] Traffic congestion

Traffic volume on the Beltway can be as high as 225,000 vehicles per day. Despite numerous widening projects during its history, heavy traffic on the Beltway is a continuing problem. The Woodrow Wilson Bridge, where eight lanes on either side are squeezed into just six lanes, is particularly onerous with miles-long backups daily during commuter rush hours. The wider 12-lane replacement bridge, under construction, is expected to open in 2008, bringing relief.

Two intersections on the Capital Beltway are ranked in the top 20 on a study of the "worst bottlenecks in the nation." They are the I-495 at I-270 interchange in Montgomery County, Maryland, ranked third overall, which receives 243,425 cars daily, and the I-495 at I-95 interchange in Prince George's County, Maryland, ranked 11th, with 185,125 cars. The Springfield Interchange, where I-395, I-95, and I-495 meet, was previously ranked fifth worst in the nation, but recent improvements have taken it off the top 20. Local commuters refer to the Springfield Interchange as "The Mixing Bowl," although this designation is reserved by highway officials for the even more complicated interchange complex adjacent to the The Pentagon on the original Henry G. Shirley Memorial Highway (currently better-known as Interstate 395) at State Route 27 in Arlington.

In April 2005, the Virginia Department of Transportation signed an agreement with two private companies to build high-occupancy toll lanes on the stretch of the Beltway between Springfield and Georgetown Pike. Maryland officials are considering such lanes on their segment of the Beltway, as well as other major commuter highways in the state. Locals who disapprove of these projects have nicknamed them "Lexus Lanes" because of the potential high price for using the lanes in exchange for by-passing congestion. These new lanes are one stage of a controversial project to widen the beltway, with the second stage involving widening the beltway to 12 lanes; opponents have called for various alternatives to this project (as well as the controversial Intercounty Connector project) which would divert many vehicles off the northern beltway, like the Purple Line mass transit route. [1]

[edit] Exit list

Exits are numbered in a counterclockwise (outer loop) direction, which is the opposite of AASHTO guidelines. However, the normal standard is overridden due to the presence of Interstate 95, which proceeds northward on the outer loop. Being a main interstate, its number sequencing (south-to-north numbering, which is in accordance with AASHTO guidelines) takes precedence, and the remaining exits are adjusted to conform.

County	Location	#		Destinations	Notes
County	Location	Old		Destinations	Notes
Maryland
Price George's	Oxon Hill	38	2B	Interstate 295 north - Washington
		38	2A	Maryland Route 210 south - Indian Head	Northbound/Outer Loop exit only
		37	3B	Maryland Route 210 (Indian Head Highway) - Indian Head, Forest Heights	Outer Loop: to north 210
	Marlow Heights	37A	4A	Maryland Route 414 west (St. Barnabas Road) - Oxon Hill
	Marlow Heights		4B	Maryland Route 414 east (St. Barnabas Road) - Marlow Heights
	Andrews AFB	36	7A	Maryland Route 5 south (Branch Avenue) - Waldorf
			7B	Maryland Route 5 north (Branch Avenue) - Silver Hill
		35	9	Maryland Route 337 (Allentown Road) - Andrews AFB, Morningside
		34	11A	Maryland Route 4 south/east (Pennsylvania Avenue) - Upper Marlboro
			11B	Maryland Route 4 north/west (Pennsylvania Avenue) - Washington
	Ritchie		13	Ritchie-Marlboro Road - Upper Marlboro, Capitol Heights
	Largo	33	15A	Maryland Route 214 east (Central Avenue) - Largo
			15B	Maryland Route 214 west (Central Avenue) - Seat Pleasant
			16	Arena Drive	Usually open only on event days at FedEx Field
		32	17A	Maryland Route 202 east (Landover Road) - Upper Marlboro
			17B	Maryland Route 202 west (Landover Road) - Bladensburg
		31	19A	U.S. Route 50 - Annapolis	Unsigned Interstate 595
			19B	U.S. Route 50 - Washington
	New Carrollton	30	20A	Maryland Route 450 east (Annapolis Road) - Bladensburg
	New Carrollton		20B	Maryland Route 450 west (Annapolis Road) - Lanham
	Greenbelt	29	22	Maryland Route 295 (Baltimore/Washington Parkway) north - Baltimore	BWI Airport exit here
			22	Maryland Route 295 (Baltimore/Washington Parkway) south - Washington, DC
		28	23	Maryland Route 201 (Kenilworth Avenue) - Bladensburg, Greenbelt
			24	Greenbelt Metro station	Southbound/Inner Loop exit only
	Beltsville	27	25	U.S. Route 1 (Baltimore Avenue) - Laurel, Beltsville, College Park	Southbound/Inner Loop exit split into 25A (north US 1) and 25B (south US 1)
	Beltsville	26	27	Interstate 95 north - Baltimore	I-95 was once proposed to run south of this interchange into Washington
Montgomery	Oakview	25	28A	Maryland Route 650 north (New Hampshire Avenue) - White Oak
	Oakview		28B	Maryland Route 650 south (New Hampshire Avenue) - Takoma Park
	Four Corners	24	29A	Maryland Route 193 west (University Boulevard) - Wheaton	Outer Loop exit only; To U.S. Route 29 north
		24	29B	Maryland Route 193 east (University Boulevard) - Langley Park	Exit 29 on Inner Loop
		23	30A	U.S. Route 29 north (Colesville Road) - Columbia	Inner Loop exit only; To MD 193 west
		23	30B	U.S. Route 29 south (Colesville Road) - Silver Spring	Exit 30 on Outer Loop
	Montgomery Hills	21	31	Maryland Route 97 - Georgia Avenue; Silver Spring, Wheaton	Inner exit split into 31A (MD 97 north) and 31B (MD 97 south)
	Montgomery Hills	20	33	Maryland Route 185 (Connecticut Avenue) - Chevy Chase, Kensington
	Bethesda	19	34	Maryland Route 355 (Wisconsin Avenue) - Bethesda, Rockville	Exit from Inner Loop is southbound only. Entrance from southbound 355 is to Inner Loop only.
		19	35	Interstate 270 north - Frederick	Outer Loop exit only
		18	36	Maryland Route 187 (Old Georgetown Road) - Bethesda, Rockville
		17	38	Interstate 270 Spur north - Rockville, Frederick	Inner Loop exit only
	Carderock	16	39	Maryland Route 190 (River Road) - Washington, Potomac	MD 190 west - 39B from Inner Loop
		16	40	Cabin John Parkway - Glen Echo	Outer Loop exit only
		15	41	Carderock, Great Falls (Clara Barton Parkway north)	Outer Loop exit only
		15	41	Clara Barton Parkway - Carderock, Glen Echo	Inner Loop exit only
Virginia
Fairfax	Langley	14	43	George Washington Memorial Parkway - Washington
	Langley	13	44	State Route 193 (Old Georgetown Pike) - Langley, Great Falls
	McLean	12	45A	State Route 267 west - Dulles Airport	Exit 45 on inner loop
		12	45B	State Route 267 east to Interstate 66 east - Washington	Outer Loop exit only, restricted to HOV traffic during morning rush hour
		11	46A	State Route 123 south (Chain Bridge Road) - Tysons Corner, Vienna
			46B	State Route 123 north (Chain Bridge Road) - McLean
		10	47A	State Route 7 west (Leesburg Pike) - Tysons Corner
			47B	State Route 7 east (Leesburg Pike) - Falls Church
	Dunn Loring	9	49A-C	Interstate 66 west - Vienna, Front Royal	Exit 49 on Outer Loop; two exits on Inner Loop: 49A (right exit) and 49C (left exit)
	Dunn Loring	9	49B	Interstate 66 east - Washington	Inner Loop only, restricted to HOV traffic during morning rush hour
	Fairfax	8	50A	U.S. Route 50 west (Arlington Boulevard) - Fairfax
			50B	U.S. Route 50 east, to U.S. Route 29 (Lee Highway) - Arlington
		7	51	State Route 650 (Gallows Road)
	Annandale	6	52A	State Route 236 west (Little River Turnpike) - Fairfax
			52B	State Route 236 east (Little River Turnpike) - Annandale
		5	54A	State Route 620 (Braddock Road)
			54B	State Route 620 (Braddock Road)
	Springfield	4C	57A	Interstate 95 south - Richmond	Exit number is signed on Outer Loop only
		4C	57A	I-495 uses its exit numbers north of here I-495 follows I-95 exit numbers east of here
		4B	57B 170B	Interstate 395 north - Washington	I-95 originally ran north of here, as part of a proposed routing through Washington
		3	173	State Route 613 (State Route 401) (Van Dorn Street) - Franconia
		3A	174	Eisenhower Avenue Connector - Alexandria
	Alexandria	2	176A	State Route 241 south (Telegraph Road)
	Alexandria		176B	State Route 241 north (Telegraph Road) - Alexandria
City of Alexandria		1	177A	U.S. Route 1 south - Mount Vernon, Old Town Alexandria
City of Alexandria			177B	U.S. Route 1 north - Alexandria, Fort Belvoir
Woodrow Wilson Bridge continue into Maryland

[edit] History

The federal government gave final approval for the construction of the Capital Beltway (also known as the Circumferential Highway in the planning stages) on September 28, 1955. The first section of the 64-mile long Beltway (including the Woodrow Wilson Memorial Bridge over the Potomac River) was opened on December 21, 1961; the highway was completed on August 17, 1964.

Originally designated I-495, in 1977 the eastern portion of the Beltway was re-designated I-95 when a proposed alignment of I-95 from New York Avenue in Washington, D.C., through Prince George's County, Maryland to I-495 was cancelled. Motorists never fully adjusted to the two halves of the Beltway having different numbers. According to Ron Shaffer of the Washington Post, "There were signs stating that to continue on the Beltway, you had to get off at the next exit, when all you really had to do was keep going straight. Lots of resistance from bureaucrats, but eventually we got dual I-95/I-495 signs on the eastern half of the Beltway."[2] So in 1989 the I-495 designation was restored to the eastern portion, making it a dual I-95/I-495.

Traveling clockwise, the Beltway is designated as the "Inner Loop"; traveling counter-clockwise, it is designated as the "Outer Loop". This parlance too has led to its own confusion, with unfamiliar motorists imagining two separate, distinct highway alignments, one some distance inside the other. At entrance ramps to the Beltway and on the on-highway signage, "Inner Loop" and "Outer Loop" shields are posted in conjunction with the route marker shields, although the terms are not emphasized in signage.

The Beltway crosses the Potomac River twice, on the Woodrow Wilson Memorial Bridge and on the American Legion Memorial Bridge.

[edit] Notes

The circumferential roadway is located not only in the states of Virginia and Maryland, but also crosses briefly through the District of Columbia over the Potomac River on the Woodrow Wilson Bridge. [3]

The Capital Beltway also interchanges with a "secret" unsigned section of the Interstate Highway System, the long lost Interstate 595 in Maryland, completed in 1995. This roadway is still signed as U.S. Highway 50. [4]

[edit] Current works

The Springfield Interchange is undergoing continuous reconstruction. A recent addition was the reconfiguration of the I-95 split from the Beltway to its southbound journey to Richmond, Virginia. I-95 now departs via a massive flyover ramp, and the same is expected for separate HOV express lanes.

The Woodrow Wilson Bridge is also being reconstructed, with express and local lanes for both Inner and Outer Loops. When completed, the new Wilson Bridge will be higher and wider than the original 1961 span that was demolished in 2006. Currently, only the Outer Loop span is open, with Inner Loop traffic utilizing the future Outer Loop express lanes.

Also, in relation to the Wilson Bridge project, its two immediate interchanges (Exit 177/US 1 in Alexandria; and Exit 2/I-295 near the Washington city limits) are being reconstructed.

The Branch Avenue (MD-5) Interchange is also undergoing inprovements.

[edit] Exit numbering

Exit numbers on the Beltway have gone through several iterations. Originally, all exits on the Beltway were numbered sequentially in a clockwise direction, starting with exit 1 for US 1 in Alexandria. After the eastern half of the Beltway was renumbered in 1977 as Interstate 95, exits on the Maryland portion were renumbered to the current format, counterclockwise with exit numbers assigned to mileposts. This caused problems because there were some exits that had the same number in Maryland and Virginia. Around 2000, this problem was solved by renumbering all of the Virginia exits. The exit numbers between the American Legion Bridge and the Springfield Interchange--Interstate 495's intersection with Interstate 395 and Interstate 95 in Virginia--became a continuation of the Maryland exit numbers from the Woodrow Wilson Bridge to the American Legion Bridge. The exit numbers between the Springfield Interchange and the Woodrow Wilson Bridge became a continuation of the exit numbers of Interstate 95 in Virginia.

[edit] Cabin John Parkway

The Cabin John Parkway, a short connector between I-495 and the Clara Barton Parkway near the Maryland-Virginia border, is considered an Interstate spur by the Maryland State Highway Administration, and is designated I-495X. The spur connects the Clara Barton Parkway to I-495 and Maryland Route 190. The parkway runs through Cabin John Creek Park and meets the Clara Barton Parkway near Glen Echo.

[edit] See also

Inner Loop, a partly-built downtown loop
Washington Outer Beltway, a planned loop outside the Beltway

Intercounty Connector, a portion of the Outer Beltway
Fairfax County Parkway and Prince William Parkway, portions of which are built on rights-of-way acquired for the Outer Beltway in Virginia.

Springfield Interchange, the complicated interchange of the Beltway, Interstate 95, and Interstate 395 in Springfield, VA.
College Park Interchange, the less complicated interchange of the Beltway and Interstate 95 near College Park, MD.

[edit] External links

	edit Auxiliary routes of Interstate 95
	Current and Future (F)	Former
	Florida - Maine - Maryland - Massachusetts/Rhode Island - New Jersey - Virginia
	Delaware/New Jersey - District of Columbia/Maryland - Florida - Massachusetts/Rhode Island - Maine - New York - North Carolina - Virginia
	Connecticut/Massachusetts - District of Columbia/Virginia - Florida - Maryland - Maine
	Delaware - District of Columbia/Maryland/Virginia - Maine - Massachusetts - New York	New Jersey - Pennsylvania
	Florida - Maryland	Virginia
	District of Columbia - Maryland - New York	Massachusetts - New Jersey - Pennsylvania
	Florida (F) - Maryland	Virginia
	Maryland - New York	Delaware - New Jersey/Pennsylvania - Rhode Island/Massachusetts - Virginia