Mappleton is a village and civil parish in the East Riding of Yorkshire, England. It is situated on the North Sea coastline in an area known as Holderness, lying approximately south of the seaside resort of Hornsea. The civil parish is formed by the village of Mappleton and the hamlets of Cowden, Great Cowden and Rolston. According to the 2011 UK census, Mappleton parish had a population of 342, an increase on the 2001 UK census figure of 249.
The parish church of All Saints is a Grade II* listed building.
In 1991, sea defences were built in order to protect the village and B1242 main road from intense sea erosion that had threatened it - Holderness is one of the most rapidly eroding areas of the UK. The cliffs had been eroded at a rate of per year. The £2 million project created two large rock groynes to halt longshore drift as well as revetments to break the waves. In order to protect the cliffs from undercutting, their gradient was also reduced artificially.
The success of this project has created a larger higher sandy beach for Mappleton, and the erosion has slowed to a point where it is no longer a threat to the settlement. Due to these sea defences, the area is directly south of the village now suffers from an even greater rate of erosion.