Have you ever wondered why The Shard in London, the tallest building in the European Union is pointed? Why didn't they build it straight up, so there would be more office space to sell?
The answer, as vlogger Tom Scott explains in his latest video, is because of London's arcane laws around sightlines. Essentially, there are certain "protected views" that prevent skyscrapers being built blocking the way. The example used in the video is the view of St Paul's Cathedral from Richmond Park in South West London - but there are a number of others, including the view of both the Houses of Parliament and St Paul's from Primrose Hill in the North.
As a result of these complex laws, there's a restricted area in the centre of town where new towers can be built - as handily illustrated in this graphic from The Economist.
As you can see - the Shard is wedged in tightly between two restricted views. So in order to meet planning requirements, the architects had to make the building slant, to maximise the space they could use without breaking the rules. As noted in the video, the so-called "Cheesegrater" tower in the heart of the City of London itself is built the way it is for the same reasons.
Protected views though are actually fairly controversial - with the battle essentially being between traditionalists who want to protect certain views for aesthetic reasons, and realists who recognise that London needs to build more if it is to get out of the housing crisis from which it is currently suffering. So who knows how long the protected views will last?