Located at the mouth of the River Aln, the village was an important trading port, mainly involved in the export of grain and in smuggling. Due to the trade in grain, the village contained a number of granaries. The port declined after the river changed course during a violent storm in 1806. This incident also resulted in the original church on Church Hill being destroyed. The church had already suffered much erosion by the river and was in a state of collapse. After the loss of the grain exports, the old granaries were converted to houses.
Today, Alnmouth is a tourist resort. It is within the Northumberland Coast Area of Outstanding Natural Beauty. The village has the fourth oldest golf course in England. The original course was established in 1869; it is believed that it was designed by Mungo Park who became the club's first professional.