Also I am thinking of taking the bus from bath to heathrow for flight home. Anyone done this? Reliable? Time needed? Thanks in advance.
Perhaps you could clarify? Are you passing through Heathrow on your way home and how much time do you have? My gut feeling is that you would need a full day and British Rail would probably be a better option than a bus.
The scheduled travel time for National Express coaches (highway buses) from Bath Spa to Heathrow varies between 1hr55min and 2hr50min. Traffic conditions can affect travel times, of course. For timetables and fares, go here.
I took the bus from Bath to Heathrow a few years ago. My flight was 10 am, so I got up very early and caught a bus about 5am. The distance is about 100 miles, so figure a couple of hours if there is no traffic. If you go later in the day, allow more time. It's cheaper and, in some ways, more convenient than taking the train. If you take the train from Bath, you would transfer to a bus (in Reading I think) for the second leg of your trip to the airport.
Polly,
Check National Express for information on travel times and fares from Bath to Heathrow. The Coach from London to Bath stops at Heathrow, so this should be an easy trip.
You could certainly use Rail also. Check Rick's England book for information on the various options.
Cheers!