Tissø

Tissø
A map of lake Tissø, the in- and outflows and the nearby towns.
Location	Zealand, Kalundborg Municipality
Coordinates	55°34′N 11°18′E / 55.57°N 11.3°E / 55.57; 11.3Coordinates: 55°34′N 11°18′E / 55.57°N 11.3°E / 55.57; 11.3
Type	Kettle hole
Primary inflows	Øvre Halleby/Åmose Å, Duemose Bæk, Tranemose Å
Primary outflows	Nedre Halleby/Åmose Å
Catchment area	417.89 km2 (161.35 sq mi)
Surface area	1,233 ha (3,050 acres)
Average depth	8.2 m (27 ft)
Max. depth	13.5 m (44 ft)
Water volume	100.64 million cubic metres (3.554×10^9 cu ft)
Surface elevation	2 m (6.6 ft)
Islands	0
Settlements	Sæby

Tissø is the 4th largest freshwater lake in Denmark, at 12.3 km². It is located on the western part of Zealand, in the municipality of Kalundborg, where some of the lake's outflow is used as cooling water for the Kalundborg Eco-industrial Park.

There are several small towns and villages near the lake, of which Sæby is the biggest at 343 citizens (2013).

Tissø means The Gods Lake, but the etymology and meaning is not obvious. Basically the name can be broken into 'Tis-sø', where 'sø' means lake in a literal and simple translation from Danish to English. 'Tis' is the more interesting part and refers to the old god Tir, who have given name to many places in Denmark like Tisvilde, Tirslund or Thisted fx., and Tissø was originally known as Tirs Lake. However the word 'Ti' is also an Old Danish word meaning God, without being specific. At some point during the Iron Age, the new god Tor took over Tirs role as a God of War and therefore Tissø was then on referred to as The Gods Lake, relying on the meaning of the word 'ti' and without being specific about which god, or gods for that matter.

In recent years, a slightly different understanding of the origins of the name Tissø have emerged. It is possible, that the name originally was Tis-ø and that the extra s have been added later on, when name-recording was needed. The pronunciation of Tissø and Tis-ø is almost the same, but the later translates as Tirs Island, referring to the area around Fugledegård on the western brink of the lake. Fugledegård was once a settlement and a magnates residence in the Viking Age and situated on a relatively high lying area, it used to be an island or islet rather. Remains of a cult-house have been excavated and there are numerous remains of animal sacrifices and religious practises at Fugledegård. There is no doubt that the area was an important religious site in former ages and there is thus a possibility, that it also gave name to the entire lake eventually.

There are many myths and folklore stories about the origin of lake Tissø.