Volkswacht Bodensee - Tokyo's all-seeing Skytree tower

The structure is an ever-present landmark at ground level, too, for Tokyoites going about their daily lives, as shown in a series of AFP photos.

Originally planned to be 610 metres high, architects went even bigger and the Skytree was certified as the world's tallest tower by Guinness World Records when it opened in 2012.

The pronunciation in old Japanese of the number 634 -- "mu-sa-shi" -- is a play on words.

It recalls the old Musashi Province, which covered a large area including Tokyo, Saitama and part of Kanagawa Prefecture, according to the Skytree website.

The name is also a reminder of the samurai Miyamoto Musashi from the late 16th and early 17th century, one of Japan's most famous swordsmen, as well as an artist and philosopher.

Guinness World Records says it defines a tower as a structure in which less than 50 per cent of the total height is useable floor space.

The world's tallest building and also the tallest freestanding structure is the Burj Khalifa in Dubai, which stands at 828 metres (2,717 feet), according to Guinness.

H.Weber--VB