If you only had 6 hours in LONDON--what would you do???

Six hours once you are in town or six hours from plane landing to plane departing?

There is a hop on and off bus double decker that drives around London to most of the imp sights.

Agree with hop on hop off bus tour suggestion. Depending on when you're there, consider making a reservation for high tea at a nice hotel. Alternatively, lunch or dinner in a nice pub.

Yes, actual time on the ground and not in the airport is important to keep in mind. Remember to include when you need to check-in and go through security on the next leg of your journey.

Also remember the time needed to get from Heathrow (or is it a different airport or even Eurostar?) to central London. If you are arriving Heathrow and take the tube, it is an hour each way. If this is the projected scenario, you could take the tube to Green Park and proceed from there to Buckingham Palace, Bird Cage Walk, Westminster Abbey and environs. Google Buckingham Palace to Westminster Abbey and click on the resulting map. You will see many options on the map, including Trafalgar Sq or the London Eye. Narrow down the specifics and check walking distances. Conceivably, you can do a nice loop ending at Green Park tube and return to Heathrow. You can visit Fortnum & Mason and Hatchard's on this loop, too. Eating: if I were looking at places in this scenario, I would try to eat either at Westminster Abbey, St. Martin in the Fields, or Fortnum.

I would also check London Walks to see if any of their tours coincide with your timing, point of arrival, and likes.

The HOHO bus is a good idea, too.

Personally I'd skip the bus tour unless you really feel that you want to only glimpse as much of London as possible...walk starting at Westminster to see st James park/Buckingham palace/houses of parliament and then walk along the Thames a bit, perhaps as far as the embankment tube.. Grab the tube to covent garden and wander around to see Piccadilly Circus/Trafalgar Square/soho ...just be outside (bring rain gear) and enjoy the atmosphere of this amazing city... You can probably walk by the most popular central sites in six hours, but trying to cram in national gallery or inside visits might take up too much time...

The HOHO bus is OK, but besides seeing the sights while sitting, you probably would not have time to stop anyplace. I would recommend getting to the Westminster Underground stop and start a walking tour, taking in Big Ben and parliment, wander over to Westminster, then up Whitehall, heading to Trafalgar Square, the National Gallery is right there, then over to Covent Garden, down to the Strand and Fleet street, all the way to St Pauls, maybe as far as the Tower of London. From there, across the river, if the day is right Borough Market, then up the south bank (Drakes ship, the Globe, the Tate Maodern, etc,) up as far as Westminster again, or hit one of the other stations as time runs out.

Figure out places you would like to spend some more time, hit a pub or two, or more; someplace to eat. Rick Steves guides have some walking tours you could piece together, but just wandering the city is a joy.

I was in the same situation as you are in. I decided to take the Hop on, Hop off Bus to the Tower of London. The Tower was jammed with people and the line went completely around the block. Then the Hop on Hop Off bus got stuck in a traffic jam. They said they weren't going anywhere for over an hour. I tried to get on the water taxie back to Westminster but they closed the river due to some big boat going up river. Then I tried to get on the Circle Line, but it was closed that day for repairs. I hope you have better luck than I did. I did find the Hop On Hop Bus very interesting and would recommend it.

Try to ride the water taxi to catch the best view of London,

If you only have six hours between one flight and the next, you really don't have time to get into London and see anything at all. It takes about an hour to get into town (and another hour back), plus time to go back through security. I wouldn't risk it.

There is a direct train that goes to Paddington Station. It costs more, but if you have limited time, it is worth it. It even comes with a money back guarantee if they don't make it within a certain number of minutes. I don't remember how long it took, but I think it was 20 minutes. You should be able to find out information on the Heathrow website.

You don't say what time of year.

I would do a bike tour - you do not have to worry about getting stuck in traffic. You can do a group or private or hire bikes - personally not a fan of seeing a place from the top of a bus - bikes get you closer.

Whichever way you choose to go - sit down with a map and map out the places you want to be sure and see and plan a route - save time for a pub stop for sure. With your limited time I would stick to seeing things from the outside - if you could get a fast track ticket for the London eye I might do that

" for high tea at a nice hotel. "

If your talking about sandwiches, cakes, scones etc, it's afternoon tea not high tea (which is now really dinner):

http://www.learn-about-tea.com/high-tea.html
http://www.timetravel-britain.com/articles/taste/tea.shtml

Alternatively, you could spend some time at Windsor.

Since I like to walk, I would go along with walking around Buckingham Palace, St. James Park, Westminster Abbey, Parliament, along the Thames -- you will feel like you are in LONDON by doing that.

With no response from the OP to the first question -- is this six hours between flights or six hours in the city itself? -- it's hard to be helpful here. With just six hours between flights you probably should stay airside and enjoy what the airport offers, rather than go through security again. With six hours in London itself you have great suggestions above from others.

Assuming you really mean six hours in London, and not six hours between planes, and also that it isn't raining like crazy I'd go for a long walk:

Take the tube to Westminster Station. There is no finer introduction to London than exiting Westminster Station. The view of The House of Parliament is fantastic. Oogle Big Ben, The Houses of Parliament and Westminster Abby. Walk up Parliament St/Whitehall to Trafalgar Square. Now take Northumberland to the river and walk through the Victoria Embankment keeping as green as possible as far as Blackfriars Bridge. Cross it and continue to the Millennium Bridge. Cross back over the river to St Paul's. It's worth the detour to approach St. Paul's from the bridge. Recross The Millennium Bridge and continue along the river to Tower Bridge. You'll pass Shakespeare Globe Theater, The HMS Belfast, and The Borough Market and the Southwark Cathedral. Cross Tower Bridge to The Tower of London. Head back from Tower Hill Station.

The walk and lunch could be done in three hours. But if you really have six, choose to see either Westminster Abby or St. Paul's Cathedral. Take a brief rest to look a Rubens while laying on a bean bag chair at the Banqueting House. At Trafalgar Square sample the National Gallery. See either the Impressionists or the Dutch Masters. You can either take an all too brief spin through The Tower of London or slow down to sample The Southwark Cathedral, The HMS Belfast, and The Borough Market. Alternatively begin by riding the London Eye. Get your tickets in advance.

I don't have great lunch recommendations because we tend to pack a lunch and picnic in a park.

If the weather is awful choose two slow or three fast of: The British Museum; either Westminster Abby or St. Paul's; The National Gallery; or a HOHO ride. You could front load this and visit between two and four places depending on how much you enjoyed the first sghts.

We will have 6 hours on the ground--coming from Eurostar station-not the airport--thanks for all the awesome responses!

What are you interested In? My walk is a good overview, though we did it just a few weeks ago and we've been to London five times now. The National Gallery is a grand European art overview. You could teach an art history course in there. I go to The Tate British just to see Moore, The Pre Raphealites, and Turner. There are other art possibilities. Visit The Banqueting House for Rubens. The churches are quite different. Westminster is Gothic and comes with a fantastic ceiling and many royal tombs. St. Paul's is Christpher Wrens masterpiece and not Gothic. The tombs there are military heros. That it survived the Blitz is a miracle. If WWI and II are of interest The Imperial War Museum (free) and The Churchill War Rooms (spendy) are the places to go. You could watch a play at the Globe on short notice if you are willing to stand.

If you are coming into London at the Eurostar Station at Euston, the National Museum is walk-able from the station. Do the Museum and maybe a pub for lunch and take tube to Heathrow. Buses get stuck in traffic.

The Eurostar comes into St. Pancras, not Euston.

I heartily concur with those who recommend a walk, rather than museums. You could take the bus from St. Pancras down to Tower Bridge, walk across and walk the Thames path upstream to Westminster Bridge, which will give you wonderful views from The Tower of London, St. Paul's, and other sights up to Parliament and Big Ben. Or walk as far as the Tate modern and cross the Millenium pedestrian bridge to see and visit St. Paul's.

But where do you need to go next---what station or airport are you departing from? And what is your plan for your luggage?

I haven't seen anywhere here (other than assumptions) where ahockema has said they are going to Heathrow. We know that they are arriving at St Pancras and that feel that they have 6 hours. That's all that we actually know.

One further thing that we do know is that they want to park in Prague.

My nickel says its a day trip from Paris. No luggage.

If I'm right be really sure to check in with plenty of time for the train back across to Europe. Eurostar doesn't take well to latecomers.

Nigel you are spot on-we are coming in through Eurostar as a day trip from Paris-will not have any luggage holding us down. I love the walking ideas--they seem very reasonable for the time we have and a chance to get a flavor. It sounds like most people recommend the Tube rather than the bus system?

what day of the week?

Buses - real buses, not the topless hohos - give a fabulous view, especially of you can get upstairs and the front row or nearly the front row. Be aware if you are especially large or have long legs, the front row upstairs has minimal legroom to go with the incredible view.

But buses are slow. But if you are there on a weekend they move somewhat faster as long as they aren't on diversion. Diversions are posted well ahead.

Tube is fast and fun for a first timer, but visibility of the city is minimal when in the tunnel. Sort of like a worm-hole. You go in one end and pop out at the other and can be a tiny bit disoriented.

Remember to check in early enough at Gare du Nord, too. In both directions all the check in, security check and both French and British Border control is before you board the train.

I love the buses but I doubt with just arriving there like that you'll really have time to figure out the bus system. If you figure out ahead of time where you want to go, and can research which lines lead where, and buy your Oyster card on the Eurostar to save time queuing at St Pancras at the ticket machines, you could do it.

If I only had six hours in London, per your title question, I'd go to a bookstore and then somewhere for tea and cake. But that's just me!

We loved the buses and used them as much as possible during our 3-week stay in London last May. They can be slow at rush hour or where there are road works, however.

Here is a nice schematic of the major central London routes and the major sites they serve:

http://content.tfl.gov.uk/bus-route-maps/key-bus-routes-in-central-london.pdf

I was going to suggest you take the 188 from Russell Square ( 2 blocks from St. Pancras ) down to the river, get off and walk the South bank in either direction. However, there is an alert on that route and others passing by Holborn or St. Paul's, advising of delays up to 40 minutes due to road works in the area. So heading west toward Hyde park would make more sense. But I would make the Westminster Abbey and Parliament area my price goal for a nice walk; or maybe Tower Bridge for more fine views from the South Bank. So maybe the Tube would be more efficient.

You could compare the cost of journeys on an Oyster card ( which requires a refundable purchase of the card plus an estimate of your usage, up to the daily cap) with a one-day paper Travelcard which would be easy. If you are using buses, remember that they do not take cash; you must have an Oystercard or Travelcard.

I don't know, 2 1/2 hours each way on a train plus 1 hour for security and check in on each end. All to ride around London for 6 hours on a HoHo bus. Doesn't quite pass my bang-for-the-buck test. And think of it like this, you're forgoing a day in Paris for that.

From St Pancras International you can also go downstairs (northwest corner of the station) (turn right when you come out of the frosted doors at Customs - if you turn left you wind up at the Underground station) and catch the Thameslink railway train a very short ride - use your Oyster card - to Blackfriars.

The new Blackfriars station is all glass and is a bridge (not on a bridge - is a bridge) over the Thames between the north bank and the south bank. You get one of the best views of the Thames in the city, high up and all enclosed in glass it doesn't even matter if the weather turns. It is one of the best things to have been recently built in London.
You can look down at the river, or over to St Pauls, look at the wobbly bridge and over to Tower Bridge - all before leaving the station.

You are then perfectly positioned for the Tate Modern, the wobbly bridge, St Pauls and the South Bank. Not far to Borough Market and Shakespeare's Globe.

I love that suggestion, Nigel!

The Blackfriers station was not completed when we were there, so I did not think of this option. It puts them right in the heart of some of London's most iconic sights.

Victoria Line Tube from Kings Cross to Green Park
Walk thru Green Park to view Buckingham Palace
Walk thru St James's Park to visit Westminster Abbey
Walk on to Westminster Bridge to view the Houses of Parliament from the Thames
Walk up Whitehall to Trafagar Square passing Number 10.
Quick visit to the National Gallery then on to Piccadilly Circus
Piccadilly Line Tube to return to St Pancras

I would cram all the touristic sights and landmarks - from Big Ben to the Buckingham Palace! But I don't know about you, I try to organize my trips as much as I can (even if I have only six hours), and whenever I'm in UK I use this to check opening times or route planning.

I think the trip is absolutely worth it to walk along the Thames and view the many iconic London landmarks. Just seeing Big Ben and the Tower Bridge will be worth it. It will be a great day trip for you!

Blackfriars is a very good suggestion. But I still suggest walking to the Tower of London from the Westminster Station. Just return to St. Pancas via Blackfriars. You will see much of London and have time to visit a couple sights in route.

I wouldn't do London as a day trip myself, but that's a cost not time issue. If I spent the money, I'd come to London as early as possible and go back to Paris as late as possible. You can have dinner in London and nap on the train.

To walk from Westminster Br to Tower Br is a lot of walking, approx 3 miles all up.

We came into London via the Eurostar from Brussels in May. The Thameslink City Station is only two stops from St. Pancras and puts you out right on Ludgate Hill in less than 10 minutes. You pop out of the station and look right and spot St. Paul's just up the street. After you tour St. Paul's interior, you can climb the dome of St. Paul's for a thrilling view of the city. There are many eating places surrounding PaterNoster square behind St. Paul's and a cafe in the crypt of St. Paul's itself. Millennium Bridge, the Tate Modern and the Globe theater are right there too. Even the Museum of London is only a 15 minute walk away. I think I would visit St. Paul's and environs and take the #15 Heritage Bus (or Tube) to the Tower and Tower Bridge, or going the other direction to Trafalger Square (depending on traffic density).

The Tower is a least two hours of power packed English history. You could then walk across Tower Bridge and explore the South Bank.

OR From Trafalger you are in easy walking distance to the National Gallery, Westminster Abbey, Parliament, Big Ben and Buckingham Palace. Iconic London scenery and sites.

Public busses are economical, frequent and fun to sit on the second deck for views, but can be slow in heavy traffic. I wound NOT use HoHo bussess for a short visit. I would use the tube and trains to zip to your entrance and departure points. And walk as much as you can. Sites are close and it's the best way imho to soak up the city. Enjoy. (Here is a link to my travel report about our 9 day visit to London with our jaunts about the city from our base near St. Paul's. http://www.travelpod.com/travel-blog-entries/georgygirl/1/1467319455/tpod.html )

Westminster Abbey and British Museum

If the trains are late and your time is reduced, visit the British Library. It's right around the corner and has lovely exhibits.

Use Rome to Rio app or Google maps to determine route and mode of transport about town. Pretty reliable on the fly info for us on our last trip.

One day from Paris to London and back, doesn’t sound like a good day to me, but I’m the person Leonard Cohen sings about in Slow. That said, I vote for mariart’s suggestion, I’d add a walk in Camden Lock Market, maybe picking up some food there. I also vote for using the Tube and “popping up” to see a few different areas. If you’re not already familiar with the Tube system, you might familiarize yourself with the order of the places you choose to visit, perhaps starting furthest away from your departure point and moving back “toward” your departure point during the day. If you’re running late you’ll be nearer rather than farther away from where you depart the city. Note Nigel’s caution viz. “latecomers”, it wouldn’t be a very happy ending to the day to not get back to Paris

I ditto djp's suggestion. We've done that walk many times. If you then have more time, you can walk along the river, either side, for views and relaxation...including seeing the tower of London. You can walk around London quite a bit in 6 hours so you know what you want to see when you return. Sounds like a fun day and a change from Paris. Along the way there are lots of pubs, cafes, restaurants so you can sit and take in the ambiance if you find the walk too lengthy. Have fun! Wray

I forgot my six hours would also include a London Walks walk and hopefully a visit to a garden.

Oh my now I've done more than I can possibly do in six hours!

Afternoon tea and a show.