Built in 1974 on the site of the old station, this 209m (686ft) steel-and-glass monolith is actually shorter than the Eiffel Tower, but better placed for fabulous views of the city - including, of course, the Eiffel Tower itself. A lift whisks you up in 38 seconds to the 56th floor, where you'll find a display of aerial scenes of Paris, an upgraded café-lounge, a souvenir shop - and lots and lots of sky. On a clear day you can see up to 40km (25 miles). Another lift takes you all the way up to the roof. Classical concerts are held on the terrace.