Despite its name, the Sea of Galilee is a lake: about 21 kilometers long and 13 wide, fed by the Jordan River from the north and drained by it to the south. Its surface lies more than 200 meters below sea level, which gives it a warm climate and a habit of sudden storms, as cooler air drops down from the hills and churns the water.
The Old Testament knows it as the Sea of Chinnereth, a marker on the edge of the land promised to Israel (Numbers 34:11, Joshua 12:3). By the first century its shores were ringed with busy towns, among them Capernaum, Bethsaida and Magdala, and with fishing crews working nets from small wooden boats. Luke calls it the lake of Gennesaret (Luke 5:1); John calls it the Sea of Tiberias, after the city Herod Antipas built on the western shore (John 6:1).


