Philip's Driver's Atlas Britain is an excellent value, concise paperback atlas containing all the map features normally included only in the more expensive road atlases. The front section has a route planner, key to map symbols, London approaches, plus a key map and distance table.
For easy navigating the atlas covers all of Britain at 4 miles to 1 inch (parts of Scotland at 5 miles to 1 inch, Orkney and Shetland at 6 miles to 1 inch). The maps clearly mark service areas, roundabouts and multi-level junctions, and in rural areas distinguish between roads over and under 4 metres wide - a boon for drivers of wide vehicles.
The town plan section includes a street plan of London plus 47 town and city centre maps, marking car parks and places of interest.
Completing the atlas is a huge index of 28,000 place names, so you can always find your desired destination.