Though an American, I've lived and worked in London for many years and booked the bus for my 19 year old cousin who had never been out of the USA. And I have to say that we really did get our money's worth! Not only can you get on and off the bus but a Thames River cruise (1/2 hour) is included and the day tickets are valid for 24 hours which is very handy.
I booked the tour online and picked up the bus at the Tower of London (having booked both together). I regret to say that I was initially put off by a rude staff member who ignored my question and kept on talking to some tourists who were queuing for another company. Not a good start.
However, once on the bus things got better and I was very impressed with where the Blue tour went - all over London! I was less impressed with the audio tour guide. While I appreciate that some non-historical information livens up a narrative and keeps people interested, there wasn't enough history/background of the area (not a mention of Cleopatra's needle which we passed at least twice!) and a bit too much about how good restaurants and shopping were.
We appreciated the 24 hour ticket as we had to end the tour early due to massive traffic in the West End (Oxford Street). We picked up the tour the next morning from where we left it and this time opted for the Red tour with life commentary. This was a bit better than the audio tour but again I thought the guide left a lot of time before doling out little bits of information. What he did say however was interesting but just not enough of that and a bit too much of banter with the tourists.
The "free" Thames cruise was far better than expected mainly due to the commentary which was not an official part of the tour according to the "guide". The "guide" was informative as well as humourous, giving a really good flavour of London - no doubt because he was a true cockney!
We also managed to pack in a free "Harry Potter" walk which lasted 1-1/2 hours. The guide here was very informative, taking us to various parts of London where parts were filmed and seemed to be well versed in the films. The guide also gave some information of the areas we were walking through and we did see some interesting parts of London where a tourist might not normally go. Very enjoyable.
The Big Bus company certainly gives a lot for the money and I can certainly recommend it for anyone who wants to get a taste of London and who may not have a lot of time or even for someone who has the time but wants an initial overview.
My only gripe (and it's a small one) is that the live guides (or maybe we were just a bit unlucky with ours) and the audio guide could give a bit more history and background on the areas to make them more memorable.
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