All the major Coach companies have stops in Cambridge. From Gatwick and Heathrow Airports the
Cambridge Coaches Service 78 or 79 is one of the most reliable. From Stansted Airport take either 78 or 75. National Express run regular trips to and from London.
To get to the Chemistry Department from the Coach Station walk down Emmanuel Street (don't forget the map with all this on!) to St Andrews Street (Emmanuel College should be on your left, Victoria Wine ahead). Turn left and walk up St Andrews street about 1/2 a mile. Turn right up Lensfield Road (just before St Mary and All Martyrs Church). The Chemistry Department is 100 yards up on your left but don't go in the back entrance, carry on walking up Lensfield Road and enter through the main entrance in the Car Park.