Than Tho Lake is located in the east of DaLat and it is 5.8 km far from the city center. In the past, the lake used to be the swamp. In 1937, the French was built the dam to retain water from Cam Ly stream then they made it a lake with an area of 8.5 ha and it provides water for the entire city Dalat. When they realized that the place was a deserted area, the French called “Lac desSoupirs”. Soupirs means sound of wind blowing in the forests, but it also has another meaning: the sight. The second, meaning seemed to make sense than the first one, so the lake has been called the name “Lake of sigh". Besides, there are also many stories embellished and the love story of Hoang Tung - Mai Nuong is the most popular one. At the time of Tay Son Dynasty, Hoang Tung, a solder, took Mai Nuong to the lake side to say good bye and he said he will come back on the victory day. But the wrong news came to Mai Nuong: Tung died in a battle. Mai Nuong then got depressed and thrown herself to the lake to die in order to keep the loyal love. In fact, he was not dead. When the Dynasty of Tay Son collapsed Hoang Tung came back and he heard the news that his beloved had died, so he throwing himself to the lake and died. Since then, the lake has name Than Tho, sigh. Sigh for the Depressed love. After 1975, has another name is Suong Mai (morning dew). But whenever talking about this place, the local people just called Than Tho Lake. Therefore, since 1990, it has been official called Than Tho Lake (the lake of sigh).