The world's longest sea bridge, spanning three territories, officially opened on Tuesday (Oct 23) to much fanfare.

Chinese President Xi Jinping had declared the Hong Kong-Zhuhai-Macau bridge officially open at a ceremony in the southern mainland city of Zhuhai. The bridge will link Hong Kong, Macau and the mainland's River Delta cities to form the Greater Bay Area.

Hailed as an engineering wonder, the US$20 billion (S$27.5 billion) structure is the central plank in China's masterplan to create and develop its own bay area to rival those in San Francisco, New York and Tokyo.

The bridge, which is built to last 120 years, measures 55km long. It features a main bridge stretching over 30km as well as two artificial islands and link roads totalling 25km.

The authorities said that the bridge is able to withstand a magnitude-8 earthquake, a super typhoon or a strike by a cargo vessel weighing 300,000 tonnes.

Here are some other impressive bridges that have been built over water.

1. Jiaozhou Bay Bridge (42.5km)

The Jiaozhou Bay Bridge, also known as the Qingdao-Haiwan Bridge, was hailed as the world's longest sea bridge when it opened in China in 2011.

According to the Guinness World Records, the bridge is resistant to damage from earthquakes and typhoons, and is designed to withstand the impact of a 300,000 tonne vessel.

The T-shaped bridge, which links the eastern coastal city Qingdao to the district of Huangdao, took four years and 14.8 billion yuan (S$2.9 billion) to build. It is supported by more than 5,000 pillars.

2. Lake Pontchartrain Causeway (38.4km)

The Lake Pontchartrain Causeway in the United States was the undisputed longest bridge over water for a long time, before the Jiaozhou Bay Bridge came into the picture.

The Causeway, which was completed in 1969, comprises two parallel bridges running side by side. It links Mandeville with Metairie in Louisiana.

It now holds the Guinness World Record for the "Longest bridge over water (continuous)", having previously held the title for the world's longest bridge over open water.

According to Louisiana news site Nola.com, Guinness World Records created an additional category for the longest bridge over water after Jiaozhou Bay Bridge was built.

The records registry told Nola.com that while the Causeway was shorter in length, it actually spanned a longer straight length of water, which resulted in the new category being created.

3. Hangzhou Bay Bridge (35.6km)

The S-shaped Hangzhou Bay Bridge, which is also located in China, was opened in 2008. It spans Hangzhou Bay on the East China Sea and connects Chinese business hub Shanghai with the port city of Ningbo.

The structure was billed as the world's longest sea crossing at the time of completion, and it cut the travelling distance between Shanghai and Ningbo from 400km to just 80km.

The bridge cost about US$1.5 billion and took more than three years to build. It also comprises a viewing platform and a 145m-tall tower that visitors can pay to sightsee from.

4. Donghai Bridge (32.5km)

The S-shaped Donghai Bridge was the first sea-crossing structure in China when it was completed in 2005. It links Shanghai to the Yangshan deep water port, and was designed to be resistant to damage from typhoons and high waves.

The bridge was reported to have cost 11.8 billion yuan.

Engineering company China Harbour, which lists the bridge as one of its projects, said the bridge is designed to last for 100 years. It added that the bridge can withstand an earthquake of magnitude 7 on the Richter scale.

5. King Fahd Causeway (25km)

The King Fahd Causeway is a series of bridges and causeways that links Bahrain to Saudi Arabia. It was inaugurated in 1986 after five years of construction, and remains the only land link that Bahrain has with the outside world. It has been credited as an important contributor to inter-Gulf trade, with several million people using the bridge annually.

The causeway crosses the Gulf of Bahrain, and was reportedly built at a cost of US$800 million.