The King Fahd Causeway is a series of bridges and causeways connecting Saudi Arabia and Bahrain. The idea of constructing the causeway was based on improving the links and bonds between Saudi Arabia and Bahrain. At 15.5 miles (25 kilometers) in length, the King Fahd Causeway Bridge is one of the longest in the world connecting the Gulf island of Bahrain to Saudi Arabia.

Initial surveying of the maritime project began in 1968. Next, in the spring of 1976, during a visit by King Khalid bin Abdul Aziz to Sheikh Isa bin Salman Al Khalifa, the two monarchs agreed to set up a ministerial committee from the two countries to work on the implementation of the project. Finally, construction began in 1981 and continued until 1986, when it was officially opened to the public.

The causeway was officially inaugurated in the presence of the Custodian of the Two Holy Mosques, King Fahd bin Abdul Aziz of Saudi Arabia and His Royal Highness Shaikh Isa bin Salman Al Khalifa, Emir of the State of Bahrain, with the latter consenting heartily to naming the bridge King Fahd Causeway.

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