55

The length in kilometres of the world’s longest sea bridge, which opened in China late last month. Stretching more than 55km, the Hong Kong–Zhuhai–Macau bridge-tunnel system consists of three cablestayed bridges, viaducts, undersea tunnels and four artificial islands.

The bridge crosses the Pearl River Delta to link Hong Kong with Macau and the mainland Chinese city of Zhuhai. The project went billions of dollars over budget and was delayed by two years.

Private cars need a special permit to drive it, but a bus ride from

Kowloon to Zhuhai is an option — a journey that previously took four hours now shaved to 30 minutes.