Lake Orestiada, Kastoria, also known as the lake is located in the North-Western part of Greece on the territory of Macedonia (district of Kastoria). On a small jutting into the lake is a Peninsula located in the town of Kastoria. Probably, the name "Orestiada" the lake has received from the mountain nymphs of orestad, although there are other hypotheses.

The lake is located at an altitude of 630 metres above sea level. Its area is 28 sq km and has a maximum depth of approximately 9-10 m. the Lake Orestiada is of volcanic origin and its age is about 10 million years. It is believed that the modern lake is only a part of a huge prehistoric body of water, whose size was 164 sq. km.

Here in 1992, was found the so-called "sign of Dispilio" - wood plaque with signs, radiocarbon analysis which showed that her age is more than 7000 years. This suggests that the area near the lake has been inhabited since ancient times. On the banks of Orestiada is an important local attraction is the Byzantine Church of Mauritii, which dates back to the XI century and is an important monument of the Greek Orthodoxy.

Kastoria lake is an important ecosystem with rare ecological environment, home to a huge number of different creatures, many of which are endangered. At the lake you can find about 200 species of birds – swans, wild ducks, herons, gulls, storks, thrushes, ibises, cormorants, starlings, Robins, and even white pelicans. The variety of fish that live in the lake (carp, carp, perch, roach, catfish, etc.) makes a very popular pastime like fishing. Also the lake is home to beavers and otters. You can meet turtles, salamanders and snakes. In the mountains surrounding the lake are inhabited by wolves, foxes, bears, wild boars and other mammals. Very diverse and fauna areas of the lake. This diversity of flora and fauna is somewhat surprising since there is a fairly developed city.

Lake Orestiada is one of the most picturesque Balkan lakes and has been classified by the Ministry of culture and tourism of Greece as a natural monument.