From Heathrow Terminal 1 train to Paddington (H&C Line)-Underground, Tube to London Kings Cross, then train to Kings Lynn. 2hrs 33min £47. From Heathrow Central Bus Station line 727 bus to Trumpington, The Busway Trumpington Park-and-Ride (Car Park), bus to Cambridge, then train to Kings Lynn. 3hrs 34min £35. From London Heathrow drive to Kings Lynn. 2hrs 10min £25.