Ovan lake is a small alpine lake in Alamut region of Alburz range, located in 75 km from Qazvin. in Qazvin province of Iran. The only tributary that flows into the lake, is a stream with the same name, Ovan, coming down from northern mounts. The north of the lake is also surrounded by three small villages, namely from east to west: Varbon, Ovan and Zar-abaad.

The deepest section of the lake is 5.7 meters and extends over 70,000 square meters. The water of Ovan lake is provided from rainwater and also the ever-gushing springs in its ground which results in very clean and transparent clear water.

The excess water of the lake which is actually overflow of this lake forms a small river which irrigates farmlands in the villages of Kushk and Ain. Most residents of these two villages either breed livestock or work their land. Ovan Lake is suitable for fishing, swimming and riding boats in summer while in fall it hosts migratory birds such as swan, goose and duck. In winter, the lake can be used for sports such as skiing and ice skating while its surface becomes slippery with ice in winter.

Ovan Lake is the largest in Qazvin province. There in the lake also live fishes like salmon, carp, and pike in addition to plants like everglade and reed that grow in its vicinity. Thanks to these beauties and natural potentials, Ovan Lake is recorded as one of the most significant tourist poles in Qazvin province and is frequented by many visitors from around the country and all over the world during the whole year especially on holidays and in summer. The fact that it is being visited by tourists and travelers has helped locals economically in various ways.