What are the top 10 must-see attractions for visitors to London?
Obviously it depends on what kind of visitor you are. A Chinese tourist is going to want to see something different to a family from Northamptonshire. But generally, overall, all things considered, which 10 places would they be?
These are the 10 most-visited attractions in London last year, according to the annual ALVA list.
1 British Museum 2 National Gallery 3 Tate Modern 4 Natural History Museum 5 Southbank Centre 6 Somerset House 7 Science Museum 8 Victoria and Albert Museum 9 Tower of London 10 Royal Museums Greenwich
That's a pretty good list of world-class attractions... but flawed, because only members of the Association of Leading Visitor Attractions are included.
Hence TfL's list of the 10 most popular attractions is subtly different.
1 British Museum 2 Somerset House 3 National Gallery 4 London Eye 5 Tate Modern 6 Tower of London 7 Natural History Museum 8 Victoria and Albert Museum 9 Science Museum 10 Madame Tussauds
Two of Merlin Entertainments London attractions now appear, the London Eye and Madame Tussauds. You might not rate them, but tourists certainly do, as the number of visitors confirms.
The Visit London website, our capital's global tourist ambassador, provides its own list of Top 10 Free Attractions.
1 British Museum 2 National Gallery 3 Tate Modern 4 Natural History Museum 5 Southbank Centre 6 Somerset House 7 Science Museum 8 Victoria and Albert Museum 9 Royal Museums Greenwich 10 National Portrait Gallery
That's almost exactly the same as the ALVA list, but the Tower of London isn't eligible because it costs, so the National Portrait Gallery edges in.
The Visit London website also has a list of Top 10 Bookable Attractions (because flogging tickets is how it makes its money).
1 Buckingham Palace Tour 2 Hop On Hop Off Bus Tour 3 Warner Bros Studio Tour 4 Kensington Palace 5 London Eye 6 Tower of London 7 Sea Life London 8 ZSL London Zoo 9 Madame Tussauds 10 The View from the Shard
Focusing on paid attractions puts a very different slant on things, and looks a lot more like a list of 'Stuff That Tourists do'. That Harry Potter tour is a naughty inclusion, though, because it's several miles into Hertfordshire.
So far we've only considered attractions you can go inside. What of iconic attractions most tourists only point a camera at, like Tower Bridge, Trafalgar Square and the Houses of Parliament? Surely some of these deserve to be included. Or London's great churches - Westminster Abbey and St Paul's Cathedral - which surely more tourists come to see than our museums?
So, combining all of the above, here's my attempt at a list of London's Top 10 Must-See Attractions.
1 Houses of Parliament 2 Buckingham Palace 3 Tower of London 4 Tower Bridge 5 River Thames 6 St Paul's Cathedral 7 Westminster Abbey 8 Trafalgar Square 9 British Museum 10 London Eye
I'm sure you'll disagree. I could be persuaded to change my mind.
And finally, a top 10 list of Must-See Attractions Only Tourists Do.
1 Madame Tussauds 2 Changing The Guard 3 M&Ms World 4 Hop On Hop Off Bus Tour 5 The London Dungeon 6 Harrods 7 Shrek's Adventure 8 Ripley's Believe It or Not 9 The Dangleway 10 Camden Market