Grodzisko, an archaeological open-air museum in Sopot, is a charmingly located open-air museum. On the hill there is a reconstructed stronghold, i.e. an early medieval defensive settlement, and by the pond - a modern exhibition pavilion presenting the oldest archaeological monuments of Sopot.

The stronghold is the oldest monument in Sopot and at the same time a branch of the Archaeological Museum in Gdańsk. An archaeological stronghold is simply a remnant of a defensive settlement (so-called stronghold). It occurs in the form of a circular or four-sided hill. The term "fort" is also used to describe a large defensive settlement (stronghold). This charming open-air museum (in this case the so-called archaeological open-air museum) is located in a picturesque setting of lush greenery and babbling streams.

The reconstructed buildings of the town are presented here: cottages, a gate and partly a palisade (a fence made of wooden poles). All the above-mentioned building elements were reconstructed precisely in the places where their relics were discovered, i.e. the remains of authentic building elements existing in the past.