Tokyo Skytree is the world's tallest tower at 634 metres, a number that's no accident — in old Japanese, 6-3-4 can be read as 'mu-sa-shi', the historical name for the region where Tokyo now stands. Completed in 2012, it replaced Tokyo Tower as the city's primary broadcast tower, but it's the observation decks at 350 and 450 metres that have turned it into one of the most visited structures on earth. On a clear day — especially in winter or after rain — you can see Mount Fuji hovering on the western horizon like a rumour of another world.
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