As some of you will know, Heathrow is very close to several rail lines, but initially wasn't connected to any. The Piccadilly line didn't make it there until the late 70s, and the spur from the Great Western Mainline to allow trains from Paddington in 1998. The planned access from the south for trains to Waterloo (Airtrack) has a secret empty station at T5, but otherwise seems unlikely to happen Possibly more likely is a western access to the Great Western Mainline, so that trains from Reading (or perhaps even Bristol/Oxford/South Wales) could get direct access to Heathrow. This is known as the "Western Rail Link". The Network Rail consultation on the project opened today, and contains quite a lot of interesting information! Even if you don't want to respond to the consultation, it's worth a quick read to see what they're planning, and what they're not!