Baltrum is a barrier island located off the coast of East Frisia in Germany. It serves as a municipality within the district of Aurich, situated in the state of Lower Saxony.
The island is positioned between the chain of the seven inhabited East Frisian Islands. It is distinguished by being the smallest island in this specific chain in terms of both land area and population size.
Baltrum covers a total land area of 6.5 square kilometres. As of 2011, the island had a resident population of just over 500 people.