The incredible £15bn bridge that includes a tunnel and stretches 34 miles across the sea

China’s Hong Kong-Zhuhai-Macau Bridge (HZMB) is a marvel of modern engineering. It currently holds multiple world records and is designed to last 120 years.

This 34-mile bridge crosses the Lingdingyang and Jiuzhou channels in the Pearl River Estuary, connecting Hong Kong with Macau and Zhuhai in China.

Made up of a series of three cable-stayed bridges, an undersea tunnel and four artificial islands, it is no surprise that the project cost an eyewatering £14.8 billion in total.

The HZMB currently holds the record for the longest sea crossing and the longest open-sea fixed link in the world.

Before the HZMB was built, the journey between Hong Kong and Zhuhai typically took four hours. Now, users can cover the distance in just 30 minutes thanks to this infrastructure, open 24 hours a day.

The structure's viaduct section consists of three cable-stayed bridges: Qingzhou Channel Bridge, Jianghai Channel Bridge and Jiuzhou Channel Bridge. The former has the longest span, at about 1,502ft long.

Jianghai Channel Bridge’s steel tower weighs about 3,100 tonnes, with the bridge’s decks totalling an incredible 420,000 tonnes. This is equivalent to the weight of 60 Eiffel Towers.

The tunnel, meanwhile, lies in a stretch of open sea with a maximum depth of 147ft, with the size of a standard tunnel segment at around 590ft long by 124ft wide and 36ft high. Each piece - precast and brought via a tug boat - weights 80,000 tonnes.

The tunnel was incorporated into the design to allow ships to pass through and runs between two artificial islands, the Blue Dolphin Island on the west and the White Dolphin Island on the east.

Construction began in December 2009 on the Chinese side and in Hong Kong two years later. Originally set to open to traffic in late 2016, the HZMB was finally completed in February 2018 and was launched to the public the following October after an inauguration ceremony attended by Chinese leader Xi Jinping.

However, a special permit must be obtained just to cross it and all vehicles have to pay a toll which, combined with high private vehicle ownership fees, means one of the most encouraged ways to cross it is by private shuttle buses.

To make the journey more complicated, drivers must use crossing viaducts to switch lanes, as people drive on the left in Hong Kong and Macau but on the right in Zhuhai and mainland China.