US climber Alex Honnold begins free solo climb of Taipei 101 | AFP

US climber Alex Honnold begins scaling Taipei 101, one of the world's tallest buildings, as fans gather to cheer him on. The 40-year-old is attempting to become the first person to scale the skyscraper in Taiwan's capital without a rope, harness or safety net. The challenge is being streamed live on Netflix.