by AIR

The closest airport offering scheduled flights is Stansted, which is 30 miles from Cambridge. A regular bus service and a direct train service run from Stansted to the city.
Stansted Airport, Heathrow Airport, Gatwick Airport, all major UK international airports

by TRAIN

There are regular train services to Cambridge from London and the major airports.
Cambridge <-> London, National Rail, Journey Planner, London Underground, London Underground Maps

by BUS

The central drop-off point for bus services is at the city bus station on Drummer Street. Full information about bus routes and timetables is available. National Express buses, Buses from airports, Local buses, Other useful links

by CAR

Visitors to the Department are encouraged to travel by train. Parking on site is very limited and is only possible by prior arrangement through your host at the Department. Please report to Reception on arrival. Cars parked on site without prior permission will be wheel-clamped. On street metered parking may be available on parts of Trumpington Street and Trumpington Road. Whenever possible please use ‘Park & Ride’ sites instead of bringing your car into the city centre.
Park & Ride, Further parking information