 As Oost is situated in the westernmost part of this municipality, to the west its outlying area borders the Meuse river and Belgium.Oost has more than 600 inhabitants and is situated south of the city of Maastricht and 3 kilometers north of Eijsden, which is the largest place in the municipality.The region around Oost has a complex history, but significantly, many centuries ago, Oost was a seignory and its own municipality and a "ban" (judicial district) of the Dalhem county.