In 1848, the dam of Melide was built on a moraine between Melide and Bissone. The A2 motorway and the Gotthard railways cross the lake there, linking Lugano to Chiasso. The dam separates the northern (27.5 km²) and southern (21.4 km²) basins. The lake retention time of the northern (11.9 years) is considerably higher than the one of the southern (2.3 years) (8.2 years on average).
Well known mountains and tourist destinations on the shores of the lake are Monte Brè (925 m) east, Monte San Salvatore (912 m) west of Lugano and Monte Generoso (1,701 m) on the south-east shore. The World Heritage Site Monte San Giorgio (1,097 m) is situated south of the lake.
Places at the lake in Switzerland (CH) and in Italy (I) include (from Lugano, clockwise):