Heathrow 6 hour layover - Go into London?
 

Hi,

I will be in London for a layover in March. I will arrive at 11pm and will be flying out at 6:30am to Dublin. Is that enough time to do any touring? I am aware that it will be in the middle of the night. Would I have enough time to get to Big Ben and back to the airport? I'm a typical tourist, I know. Any suggestions would be appreciated, thanks!

I think your best bet will be the Heathrow Express to and from the airport:

https://www.heathrowexpress.com/timetable-schedule

However once you get to London, you'll have the problem of getting around town. The tube will shut down late at night, so you'd have to walk, take a taxi or car service, or take a night bus, or some combination of these.

Actually I guess you probably have the option of taking the Piccadilly line into town. But you'll need to check when that stops running.

Is your luggage booked through, or will you have to reclaim it and check in again for your Dublin flight? How long do you really have between getting through immigration and having to check-in/reboard?

The last tube train into central London leaves Heathrow around 11.30pm, and they don't start running again till after 5am. The last Heathrow Express (not cheap) leaves Heathrow a little later, but they too don't start running again until gone 5am. Even if the timing works for you, you'd be committed to wandering around central London for four hours in the middle of the night. There are night buses that could possibly be used to give you a drive-by of some of the sights (but would you be able to get an Oyster card at that time of night, or would you have to pay the deterrent cash fares?). If it were me I'd be far happier just booking into an airport hotel for a few hours' shut-eye.
www.tfl.gov.uk
www.heathrowexpress.com

W/ that schedule -- traveling in to London makes no sense at all. By the time you clear immigration and stow your carry ons, it will be after midnight. The HEX is very expensive and only gets you to Paddington -- and there is nothing to see/do there.

Just book a LHR hotel and get a little sleep . . .

Even if it was 11:00am and your onward flight was 6:30pm I'd recommend staying at the airport. As it's overnight I'd suggest getting a shower and a couple of hours kip. Given that you will need to be awake by about 4:00am the Yotel which is in the airport may be the best option

Thank you everyone. I wasn't sure if it was a realistic feat with all of the "obstacles" to go through in airports. I'm sure I'll appreciate the choice to sleep when I get there!