The island castle is a variation of the water castle

Water castle

A water castle is a castle or stately home whose site is entirely surrounded by moats or natural waterbodies. Topographically water castles are a type of lowland castle.There is a further distinction between:...

. It is distinguished by its location on an artificial or natural island. It is a typical lowland castle

Lowland castle

The term lowland castle or plains castle describes a type of castle based that is situated on a lowland, plain or valley floor, as opposed to one built on higher ground such as a hill spur...

.

Because the island on which the castle was erected is separated from the shore by at least two bodies of water, artificial defences such as moats or shield wall

Shield wall (fortification)

A shield wall refers to the highest and strongest wall of a castle where it is clearly distinguished from the other curtain walls of a castle. The shield wall serves to protect the side from which the main attack is expected...

s were usually unnecessary if the castle was surrounded by flowing water. Such castles could therefore be very easily and cheaply built. Many island castles in lakes were, however, relatively easily captured in winter if there was an ice sheet thick enough to support attacking troops, because they were often rather poorly fortified.

The best-known island castle in Germany is Pfalzgrafenstein Castle near Kaub

Kaub

Kaub is a town in Germany, state Rhineland-Palatinate, district Rhein-Lahn-Kreis. It is part of the municipality Loreley. It is located on the right bank of the Rhine, approx. 50 km west from Wiesbaden. It is connected to Wiesbaden and Koblenz by railway. Population 1100...

. The only Gothic

Gothic architecture

Gothic architecture is a style of architecture that flourished during the high and late medieval period. It evolved from Romanesque architecture and was succeeded by Renaissance architecture....

 water castle in Europe is Trakai Castle

Trakai Island Castle

Trakai Island Castle is an island castle located in Trakai, Lithuania on an island in Lake Galvė. The castle is sometimes referred to as "Little Marienburg". The construction of the stone castle was begun in the 14th century by Kęstutis, and around 1409 major works were completed by his son...

 in Lithuania

Lithuania

Lithuania , officially the Republic of Lithuania is a country in Northern Europe, the biggest of the three Baltic states. It is situated along the southeastern shore of the Baltic Sea, whereby to the west lie Sweden and Denmark...

.