The most difficult bridges riddles

Hamburg's many streams, rivers and canals are crossed by some 2,500 bridges, more than London, Amsterdam and Venice put together. Hamburg has more bridges inside its city limits than any other city in the world. The longest one (picture above), Köhlbrandbrücke is 3940 metres long.

The first modern bungee jumps were made on 1 April 1979 from the Clifton Suspension Bridge in Bristol, England. It was inspired by the "vine jumping" ritual carried out by certain natives of Vanuatu. The jumpers were arrested shortly after, but continued with jumps in the US from the Golden Gate Bridge and the Royal Gorge Bridge, spreading the concept worldwide.

The Erasmus Bridge is a reflection of the industrial character of Rotterdam and helps in organizing traffic flows, operating as a last crossing point between the Northern and Southern parts of the city. It was used in several recognizable events such as Tour de France or Red Bull Air Race.

The Hong Kong–Zhuhai–Macau Bridge (HZMB) is a 55-kilometre (34 mi) bridge–tunnel system consisting of a series of three cable-stayed bridges, an undersea tunnel, and four artificial islands. It is both the longest sea crossing and the longest fixed link on earth. The HZMB was designed to last for 120 years and built with a cost of US$ 18.77 billion.

The Ponte Vecchio is a medieval stone closed-spandrel segmental arch bridge over the Arno River, in Florence, Italy, noted for still having shops built along it, as was once common. Butchers initially occupied the shops; the present tenants are jewelers, art dealers and souvenir sellers. The Ponte Vecchio's two neighbouring bridges are the Ponte Santa Trinita and the Ponte alle Grazie.

The Vasco da Gama Bridge is a cable-stayed bridge in Lisbon, the capital of Portugal. It is the second longest bridge in Europe after the Crimean Bridge with a total length of 12.3 kilometres (7.6 mi). The bridge was opened to traffic on 29 March 1998, just in time for Expo 98, the World's Fair that celebrated the 500th anniversary of the discovery by Vasco da Gama of the sea route from Europe to India.

The Golden Gate Bridge is a suspension bridge spanning the Golden Gate strait, the one-mile-wide (1.6 km), one-point-seven-mile-long (2.7 km) channel between San Francisco Bay and the Pacific Ocean. The structure links the American city of San Francisco, California to Marin County, carrying both U.S. Route 101 and California State Route 1 across the strait. The bridge is one of the most internationally recognized symbols of San Francisco, California, and the United States. It opened in 1937 and was, until 1964, the longest suspension bridge main span in the world, at 4,200 feet (1,280 m).