The four most frugal town cars

Official government fuel consumption figures for every new car include one for urban driving, but you can never expect to match the figure in real traffic, because the official test is based on unrealistically gentle rates of acceleration and very low speeds. This is likely to change in the next couple of years to reflect real-world conditions.

But the official figures are still a useful guide. Not surprisingly, they reveal small cars with diesel engines to be much the most economical. Diesels have a further advantage in that they function at virtually full economy as soon as they start from cold, whereas a petrol engine is much thirstier when cold than when warmed up.

First: the VW Golf Ecomatic, which scores 61.4mpg on the official urban test. This Golf has a diesel engine that switches itself off when the car stops, and restarts automatically when you press the accelerator. It also lacks a clutch pedal, though the gear-change is a normal manual system. You drive it as you would any other car, except that you can forget about doing anything with your left leg. Uncanny, but true. If the engine's stopping and starting irritates you, as well it might, you can switch the system off. Trouble is, you then use more fuel while the engine sits idling in stationary traffic.

Second: the Citroen AX 1.5D, with 55.4mpg. A relatively large, unstressed engine in such a light car is a fine recipe for fuel economy, especially when the engine is an extremely economical diesel. The diminutive AX is lively and agile, too, which makes it a great town car.

Third: the Peugeot 106 1.5D with 51.4mpg. Powered by the same engine as the Citroen, the Peugeot is heavier and therefore slightly slower and thirstier. Several trim levels are available, as they are with the AX.

Fourth: the VW Gold TDi, with 50.4mpg. Not only is this direct injection, turbodiesel Golf very economical, it is also rapid, with tremendous pulling power from low speeds. If your town driving includes steep hills, this is the economy car for you.