Grendon Underwood is a village and civil parish in west Buckinghamshire, England, near the border with Oxfordshire. The village sits between Woodham and Edgcott, near the Roman road Akeman Street, and around 10 miles (16 km) north-west of Aylesbury. At the 2011 Census, the population of the civil parish was 1,625.

Long Crendon is a village and civil parish in west Buckinghamshire, England, about 3 miles (5 km) west of Haddenham and 2 miles (3 km) north-west of Thame in neighbouring Oxfordshire. The village has been called Long Crendon only since the English Civil War. The "Long" prefix refers to the length of the village at that time, and was added to differentiate it from nearby Grendon Underwood, which used to be known as "Crendon". This name is Old English and means 'Creoda's Hill'.