Châteaulin is a small, but lively town in the Finistère department of Brittany in northwestern France. It is located on the banks of the Aulne River, which flows into the Bay of Biscay. The town is a popular stop for tourists who are interested in the history and culture of Brittany, and it is also a convenient base for exploring the surrounding countryside. Châteaulin is home to a number of interesting historical sites, including the ruins of a 12th-century castle and a 16th-century church. The town is also known for its traditional Breton music and dance, and for its delicious seafood.