A5100

The A5100 is a short A-road in north London. The road was originally unclassified but gained its number in the late 1920s, presumably as a link to the then-new A5088 Watford Bypass (present A41).

The road begins, or its classification begins anyway, off the A5 High Street Edgware as Station Road, although in many ways the A5100 is the real high street in Edgware now. The other side of the junction is the B461 Whitchurch Lane which goes towards Canons Park (and leads to Belmont, although that section is totally unclassified).

The first section is fairly busy with a junction with the Broadwalk Centre, the main shopping centre in Edgware that opened in 1989. Edgware Station follows shortly and there are a lot of buses turning here. The station itself is the terminus of the Northern Line, but it wasn't always planned to be that way: the intention was to extend the line towards Elstree and also to complete the branch from Mill Hill East.

Once past the junction of Edgwarebury Lane the road changes its name to Hale Lane. Most of the through traffic runs on the parallel A41 but at least the A5100 only has mini-roundabouts with Edgwarebury Lane and Broadfields Avenue, whilst the A41 traffic is subjected to two sets of traffic lights. After Broadfields Avenue it's pretty much the end of the shops and the road is residential, so you move along quite steadily, passing the brook and Stoneyfields Park.

After you hit a double mini-roundabout with the A5109 Deans Lane / Selvage Lane the name of the road is still Hale Lane but you've crossed the London postcode boundary and are in Mill Hill, NW7. The road remains residential (apart from a school on the left) until the next mini-roundabout where Hale Lane ends. The right branch is Bunns Lane, which is an unclassified semi-main road - this leads you towards Grahame Park Way (for the RAF Museum and Colindale) whilst Bunns Lane itself passes underneath the A1 and towards Copthall crossing Page Street and eventually out towards Mill Hill East.

Motorway and railway bridges

The A5100 itself doesn't have long to go as it bends to the left into Mill Hill Broadway, which is also the name of the station on the Thameslink Line. At that point the M1 is overhead running parallel with the railway (as it does until its end at Staples Corner). The A5100 passes through the busy shopping area of Mill Hill to meet the A1 (which here is the dominant number in a multiplex with the A41) at Mill Hill Circus.

So the A5100 begins at the A5 and ends at the A1. The A306 also runs (with both ends) between two single-digit A-roads: A3 to A4. Are there any others?