Originally Posted by
Abidjan
Yes, you can. Just take the Heathrow Express one stop, from T4 to T3. Free transfer. The elevator to go down the the train is located to your immediate left just as you exit the covered walkway between the hotel and T4.
One minor correction - Heathrow Express goes between T3 to T5, Heathrow Connect goes between T3 and T4. The Connect runs at 30 minute intervals, not quite as handy, so if using the T4 Hilton, leave a little earlier to get to T3. Even more of a pain if you are going to T5, you have to go to T3 and change trains for T5.