Layover at Heathrow

If you decide to stay overnight, park your luggage at an airport hotel where you plan to spend the night. You will have plenty of time to get into London for most of the day and return to your hotel in the evening. See if you can buy a daypass for the Tube so you can zip around London. Study up to decide what you want to see. Check with a London or England tour book. Some years ago I took a day trip into London and had time to visit the British museum, Buckingham Palace, and a couple of other places.

I agree, I think you would have to be there by 4:45 am for that morning flight. I'd probably stay over and go into London, especially since you've never been before. You never know when you'll get another chance.

Thanks Swan and Maggie! I'm getting excited about this possibility. Looking on the web, I would arrive at Terminal 3 on AA and would depart Terminal 4 Alitalia. I was thinking the Yotel in Terminal 4 would be a good overnight location for sleep before departing because it is in the same terminal as I depart. If I check in at 9pm and out at 4am it would be 65 pounds. That would work particularly well if I could check my bag through from RDU to Rome. Then I'd just have a small carry on to lug around with me and could leave directly from Terminal 3 for London. In the evening I would return to Heathrow, but to Terminal 4, and check in at the Yotel. My concern with the above is that I don't know if I can check a bag through and, if so, would the length of time increase the risk of my bag getting lost, etc., since it would be 24 hours from arrival at Heathrow to departure. A second option would be to go from Terminal 3 to 4 on arrival and check in at the Yotel, and leave my bags. Downside is that since Yotel rates are based on the number of hours the room is used, my hotel cost increases almost 30 pounds from 65 pounds to 93. A third option, which may be the least convenient, would be to go on arrival from Terminal 3 to Terminal 4 and leave luggage for 8.50 pounds per bag in storage, then go from Terminal 4 into London, and pick up the bag(s) when I return that evening to check in at the Yotel. Any thoughts/advice would be appreciated!!

Not sure about the luggage issue... call the airline and see if it can be check through. But...definitely... take the opportunity to see London in a few hours! I did this once a number of years ago and got a good overall quickie look at the city. Another time, a friend and I did it because we took a bump and got last minute tickets for Les Mis (have to admit I dozed off) but it was still worth it.

I would go to London! You will love it! Do stay at the airport, though. The tube will NOT be running early enough the next morning. There's a journey planner right here http://www.tfl.gov.uk/modalpages/2625.aspx
so you can check when the last train from the city is the night before. You mention that you are on a budget. Having just come back from London, I can confirm that it is indeed a spendy city! That being said, so many of the major things are FREE: the Tate Modern, the Tate Britain, the V&A, the British Library, the National Gallery and the National Portrait Gallery, the Museum of London... and of course it is free to explore a local market, and to walk along the Strand, or window shop on Oxford Street or Regent Street or the King's Road. A pub lunch should not be pricey, and is a quintessential London experience. Have a GREAT time!