The Gopło lake is a lake located in North-Central Poland, near the town of Gniezno. The pond is located within the protected Gopło landscape Park. The lake is 12 miles South of Inowrocław and extends over 37 kilometers from North to South.

The name of the lake derives from the medieval Slavic tribe of goplan that lived in the local land.

This is a lake of glacial origin with a low coastline, with numerous bays and peninsulas, in some places the shoreline is marshy. It is home to catfish, the biggest freshwater fish in Europe. The surrounding landscape consists mainly of meadows and forests in the southern part of the lake. The average depth of the lake ranges from 3, 6 to 4 meters, 7 meters and the maximum depth of the lake is about 17 meters.

The lake Gopło and landscape Park of the same name, are a tourist attraction of the region. Nearby are the ruins of the former Royal castle Kruszwica, built by Casimir the Great in the mid-fourteenth century. As of today only the Mouse tower, the castle was repeatedly destroyed and is now in ruins.