Mill Hill driving test centre

Mini-roundabouts are the signature of this area. There are 34 of them in the streets around the centre against 38 signalled junctions, an unusually even split, and only four conventional islands nearby, at Beverley Drive, Knightswood Close, Charcot Road and Brent Street. On the practice loops on this page the roundabout count per loop runs between two and four, so what you meet far more often is a mini or a plain give-way. Signal for the exit, look right properly, and steer round the painted circle rather than over it.

The limits set this centre apart from the rest of London. Around four-fifths of the roads mapped nearby are 30 mph and only a small share is 20, so the traffic moves. Watford Way carries the fastest driving, with dual carriageway for the longer routes, while Bunn's Lane, Page Street, Wise Lane and Selvage Lane carry the ordinary town part of the test at 30.

The estates are the other half. Grahame Park Way, Field Mead, Clayton Field, Lanacre Avenue and Heybourne Crescent form a grid of wide residential roads with parking on both sides and turnings close together. Most manoeuvres are set there, and a pull-up on the right or a bay park has real parked cars to work around rather than an empty kerb.

Sixty-seven schools sit inside the area covered, so timing matters more here than at most centres. A slot in the middle of the afternoon puts you into the school run: cars stopping where they should not, doors opening, children crossing between parked vehicles. If you have a choice of times, mid-morning is the calmer test.