San Francisco\'s  Golden Gate Bridge San Francisco on Sunday will mark the 75th anniversary of the Golden Gate Bridge, the distinctive orange vermilion structure that attracts some 10 million visitors each year. The city\'s waterfront is hosting a massive celebration complete with dance, music, vintage cars and motorcycles, as well as a fireworks show for a grand finale showcasing the iconic bridge at the entrance to the San Francisco Bay.
But organisers worry the bridge could be a no-show, should a thick fog cloak the attraction as it does on many days here. For now, the weather forecast calls for a partly cloudy Sunday.
The celebrations are taking place 75 years to the day after the bridge was opened to the public: to pedestrians on May 27, 1937, and to traffic the next day. At the time, the Golden Gate was the world\'s longest suspension bridge.
Dreamt up by engineer Joseph Strauss, the bridge distinguishes itself by its unique colour, chosen by architect Irving Morrow and dubbed International Orange.
The paint originally ensured visibility for passing ships and served as a sealant to protect the bridge from the salty mist from the Golden Gate Strait after which it was named, the entrance to the bay from the Pacific Ocean.
Construction of the bridge took four years. Some 1.7 miles (2.7 kilometres) long, it is 90 feet (27 metres) wide and its two towers reach 746 feet above sea level. Traffic is suspended at 220 feet from the water.
Pedestrians and cyclists can access the bridge.
But the span also has a grim history as a popular place to commit suicide.
An estimated 1,600 people have died there in instances where the body was recovered, with many more unconfirmed, according to the Los Angeles Times.
Last year alone, 37 people died after jumping off the bridge - the fourth highest number since it opened, the newspaper said, citing data from bridge authorities.
Events marking the bridge\'s anniversary are also taking place all year long, and a new visitor center was opened in early May at the southern entrance.