Thornton in Lonsdale is a village and civil parish in the Craven District and ceremonial county of North Yorkshire in England. It is very close to the border with Cumbria and Lancashire and is 1 mile (1.6 km) north of Ingleton and 5 miles (8.0 km) south-east of Kirkby Lonsdale, and has a population of 308, falling to 288 at the 2011 Census. Its main claims to fame are the Marton Arms pub and St Oswald's Church, Sir Arthur Conan Doyle married his first wife at this church in 1885 and held his reception at The Marton Arms before setting off to Ireland on honeymoon. Doyle's mother resided at nearby Masongill from 1882 to 1917.