The lake occupies about 197 hectares area located on the way between Surabaya – Ponorogo or it takes about 90 minutes drive from Surabaya. It is located at Grati Tunon village, Grati subdistrict. It's about 16 km east of Pasuruan. The lake has mount Tengger’s beautiful scenery. According to a legend, the origin of Grati Lake resembles to the origin of Pening Lake.
It has available recreational facilities such as boats and floating fishing net pond (keramba apung) used for breeding fresh water fish such as gurami, mujair, nila merah, etc. Ranu lake produces lempuk fish (a kind of small anchovy), which only can be found in this place.
The visitor can enjoy their time in this lake by doing some activity such as; fishing, walking around, and the others. This lake is the biggest lake in Pasuruan and often visited by local tourists, just to show the fisherman harvest their fishes.