BARCELONA (Reuters) - French "Spiderman" Alain Robert scaled one of the tallest skyscrapers in Barcelona without a harness on Friday.

Bystanders and police watched as the 54-year-old climbed up and then descended the Torre Agbar, a glass-covered office building known for its night-time illuminations, completing the feat in around one hour.

The urban climber is famous for his daredevil, harness-free approach to scuttling up buildings with nothing more than some chalk on his hands and climbing shoes on his feet.

Robert has conquered over 100 structures worldwide including San Francisco's Golden Gate Bridge, Dubai's Burj Khalifa complex, the Eiffel Tower in Paris and the Sydney Opera House without safety equipment.

(Reporting by Albert Gea; Writing by Amanda Calvo; Editing by Sonya Dowsett/Mark Heinrich)