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The lake is 6.2 ha in size, with a shoreline 1.2 km long.
On the shore of the lake there is a holiday village Niinsaare.
Lake Niinsaare is located 0.5 km north-west of Lake Kurtna Nõmmejärv. It used to be a 7.7 ha (19 acres) closed lake. In 1963, a ditch was dug in Lake Mustjärve from Lake Kurtna Suurjärvi, which caused the water level in Lake Niinsaare to drop significantly. By the summer of 1968, at least 50% of the lake was dry.
References
Niinsaare järv Eesti looduse infosüsteemis (vaadatud 21. märts 2012)