Euston Underpass
| Euston Underpass | |||
| Location Map ( geo) | |||
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| The underpass in 2007 | |||
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| From: | Euston Square Tube Station | ||
| To: | Warren Street Tube Station | ||
| County | |||
| Middlesex | |||
| Highway Authority | |||
| Transport for London | |||
| Junction Type | |||
| Modified Diamond | |||
| Junctions related to the A400 | |||
| Archway • Britannia Junction • Cambridge Circus • Charing Cross (London) • St Giles Circus • Trafalgar Square | |||
The Euston Underpass is a section of the A501 where it passes under the A400 grade-separated. It is part of the London Inner Ring Road so marks the congestion-charging zone boundary although due to turning restrictions and one-way systems, traffic heading westbound on the ring-road may briefly enter Gower Street, then turn right into Grafton Way and right again into Tottenham Court Road in order to cross the junction to get to the A400 Hampstead Road, which is a two-way road and is primary. At this point the A400 splits into two one-way streets, as previously mentioned, Gower Street southbound and Tottenham Court Road northbound.
The underpass runs adjacent to the Metropolitan Railway (also carrying the Circle and Hammersmith & City underground lines). The existence of this railway just under the surface controlled a lot of the design of this junction, especially the underpass.
The underpass has two lanes in each direction and has a speed limit of 30mph, regulated by cameras on entry where traffic tends to speed up. There are often queues on exiting the tunnel, particularly on its western exit where it meets the junction of Great Portland Street and the A4201 Albany Street.
Routes
| Route | To | Notes |
| Holloway, Camden Town | ||
| Ring road (west), (A41, A40), Kilburn | ||
| Ring road (east), (A1, A10, A11), The City, Euston, Kings Cross | ||
| West End, Westminster, Holborn | Congestion Charge applies after Grafton Way (the southern edge of the one-way system associated with this junction) |
