Alnmouth is a city in Northumberland, England. It is located about six kilometers southeast of Alnwick at the mouth of the Aln in the North Sea. Alnmouth was probably founded around 1150 by William de Vesci, Lord at Alnwick Castle and Sheriff of Northumberland. In 1207 Alnmouth got the market right. In 1806, the Aln after a heavy storm changed its course and separated the village in two parts. In 1860, the Royal Meteorological Society established a weather station in Alnmouth. The Alnmouth train station on the East Coast Main Line is located about 1.5 west of the town in Hipsburn and is officially called Alnmouth for Alnwick. The writer Val McDermid lives in Alnmouth.