London Bus Similar to Paris' #69?

The sights in London are spread over a larger geographical area than Paris, so it's not as simple as one bus as in Paris.

Last year the handy bus routes in London were:
9
11
15
23 & 159
24
38
RV1
148

Rick explains all this with details in his guidebook London.
The other HOHO bus tours are from Original and Big Bus, these are double-decker bus tours and they cost.

On the 9 and 15 route you may be lucky enough to catch one of the iconic old Routemaster buses.
http://www.londonupclose.com/routemaster-bus-heritage-routes-london.html

A bit more detail on some of these routes in central London:

9: Aldwych out into SW London. Within the centre, see Strand, Trafalgar Square, St James's Palace, Piccadilly, Knightsbridge, Albert Hall, Kensington (note that old-style Routemaster buses are NOT operated on this route any more)
11: Liverpool Street to SW London. City, St Paul's Cathedral, Fleet Street, Strand, Trafalgar Square, Whitehall, Parliament, Westminster Abbey, Westminster Cathedral, Sloane Square, King's Road
15: E London to Trafalgar Square. Tower of London, City, St Paul's Cathedral, Fleet Street, Trafalgar Square. Old-style Routemaster buses operate on this route from the Tower to Trafalgar Square.
24: Victoria to Hampstead. Victoria, Parliament, Whitehall, Trafalgar Square, Charing Cross Rd, Tottenham Court Rd, Camden Town, Hampstead
38: Victoria to NE London: Victoria, Piccadilly, Shaftesbury Avenue, Islington
RV1: Tower to Covent Garden. Via South Bank of river, but it goes behind all the big South Bank attractions so less scenic than you'd expect. Good if you don't want to walk along the river, though.

The next to last page of the most excellent official guide http://www.tfl.gov.uk/cdn/static/cms/documents/london-visitor-guide.pdf from the TfL shows the common tourist buses in central London and where all the major attractions are. The whole little booklet is worth downloading and printing out.

The same map also appears online at http://www.tfl.gov.uk/maps/visitors-and-tourists

Another vote for riding around on the 11, the 15, and the 9.

Thanks so much for all the info! I'm embarrassed to admit that I haven't yet checked the RS guidebook ... because my daughter and her boyfriend currently have it :-D We divided up the books (Paris/London/Dublin) so that everyone could flip through and get an idea of what they'd like to see in each city, and the London book hasn't made its way back to me yet.

All excellent suggestions, thank you!

Not sure if you're specifically looking to 'travel like the locals' for the experience, or looking for a cheaper alternative to the many open top, hop on hop off tourist buses costing around £20 for 24hrs. It's likely you're talking about Central West London and the tourist buses there are great. There are 100's of different public transport bus routes in London and even I get confused sometimes, and my feeling is, you're not necessarily going to see very much squeezed in with everyone else, it's more than likely you won't even get a seat, especially during busy times, which is more or less always.

If you're able, walking is by far the best way to see the city. All the most famous stuff if fairly close together, and easy to find as there are signs everywhere. I'd always take the tube in preference to the bus. A Zone 1, or 1-2 Travelcard will give you unlimited free bus travel also. It's almost impossible to get lost on the tube, not so impossible on the buses.

Walking mostly, tubes for longer distances and Black Cabs if you get lost or tired, will work well.

Thanks, Mike! We'll be staying very close to Kings Cross/St. Pancras, so we were planning to use the Tube for anything not within walking distance ... but the one thing I always liked about the #69 bus in Paris is that you got to see a bit of the city during your trip, which is the one thing you don't get with the (more efficient) Metro.

So maybe we'll just do a trip or two on one of the "hot spots" bus lines, and stick to the Tube for the rest :-)

Well there are pretty good buses at Kings Cross, too.

The 10 goes past Russell Square for the British Museum, along Oxford Street for the shopping, around Marble Arch, down Park Lane and near Buckingham Palace, Hyde Park Corner, to Knightsbridge for Harrods, the Princess Diana Memorial Fountain, the Albert Memorial, the Royal Albert Hall, and past Kensington Palace, among others.

The 43 goes past Wesley's Chapel (origin of the Methodist Church), through the City of London (the Square Mile) near St Pauls Cathedral and the Tower of London, over London Bridge, near the Globe Theatre and the Tate Modern, past the Borough Market for London's best food market where it terminates at London Bridge Station.

The 63 is a good short route to the City and Fleet Street passing the base of Ludgate Hill for St Pauls Cathedral, crossing Blackfriars Bridge to the Elephant and Castle near the Imperial War Museum.

The 59 goes down Woburn Place right through Russell Square for the British Museum, then near the Sir John Soane Museum then past Somerset House, the home of The Courtauld Gallery and all sorts of other arts and culture features, and then over Waterloo Bridge.

You can even take the 394 over to Shoreditch and the fabulous Geffrye Museum - well worth seeing for its rooms furnished century by century in ancient alms houses, and furniture, furniture, furniture - at Hoxton.

and several more, so you aren't condemned to the Tube and its tile walls ... unless you want to....