Venice, Italy : This image from the Advanced Spaceborne Thermal Emission and Reflection Radiometer on the Terra satellite, acquired on Dec. 9th 2001, shows the watery city of Venice in spectacular detail, using false-color image enhancements that bring out the details of water and vegetation. The city of canals, Venice stretches out across numerous small islands in a marshy lagoon along the northeastern Adriatic Sea. The heart of Venice is on the island known as the Rialto, the largest island in the lagoon. Rialto is split by the Grand Canal, which follows the path of an ancient river. The Grand Canal winds through the city for about 3 km, dividing it into two nearly equal sections The city is somewhat protected from the open sea by a row of sandbanks known as the Lido (east of Rialto); however, the city is continually under threat of flooding and erosion, and has been experimenting with tidal control measures for more than a thousand years. Four hundred bridges cross the labyrinth of canals that form the 120 islands of Venice. All traffic in the city moves by boat. Venice is connected to the mainland, 4 km away, by ferries as well as a causeway for road and rail traffic.