|Length:||1.3 miles (2.1 km)|
|Meets:||A13, A200, B205|
|Route outline (key)|
The A101 comprises the Rotherhithe Tunnel and its associated slip roads.
The tunnel was constructed between 1904 and 1908, and is therefore newer than the original Blackwall Tunnel. Footways on each side of the tunnel section allow pedestrian access.
Starting at traffic lights on the A13 in Limehouse, the A101 heads south and immediately goes under the DLR. This first section is dual-carriageway but through traffic needs to be in the right-hand lane as the left lane provides local access only. On the far side of the railway bridge the right-hand lane moves to the right to pass through a safety barrier next to a tunnel warning sign. Now with a 20 mph limit and average-speed cameras, the road bends to the right and descends into a cutting before entering the tunnel proper. The entrance is adjacent to Butcher Row and there are steps leading down from that road to the footway on the A101.
The tunnel, S2 and brick-lined throughout, bends left to go under the river then right on the far side as it climbs into Rotherhithe. Again at the tunnel mouth there are steps up to the public road. The cutting runs parallel to the B205 as it climbs and ends at a roundabout where it meets that road and the A200.