City Hall, London

Sometimes it feels like London’s architects are playing a game: “How can we make visitors feel like they’ve stepped back in time and into the future at the same time?” City Hall is a perfect example of that. Perched by the river, this sci-fi-looking bubble might seem a little odd at first, but give it a minute, and you’ll start to appreciate just how sleek and clever it really is.

Dreamed up by superstar architect Norman Foster and completed in 2002, this 10-story, glass-and-steel structure leans to one side like it’s striking a pose. It’s not just showing off, though - the design is ultra-efficient, taking up far less space than a normal building and using only a quarter of the energy of its more old-school neighbors. Pretty smart for something that looks like it rolled out of a future London skyline.

Fun fact: this was the first time the public got a say in picking the design. And visitors today can still climb the spiral walkway to the second floor to spy on the action below - or just grab a coffee and soak in the atmosphere. As for "London’s Living Room" on the 9th floor, the views from there are absolutely spectacular, but it’s usually off-limits... unless you time your visit for Open House weekend (the third weekend of each month).

Before you wander off, make sure to check out The Scoop - the outdoor amphitheater just next door. From June to September, you can catch free plays, movies, and concerts there under the open sky.

Quick tip: Don't miss Fiona Banner’s shiny black Full Stops sculptures nearby - giant punctuation marks in bronze, making even grammar feel epic...