Some 403 ft (123 m) high, the hillock of Houlgate - which closes the Drochon valley to the east - was once an arid hill. It was wooded by the Société de Construction Immobilière (Real Estate Construction Company) that initiated the urbanization of the right bank of the Drochon in the second half of the 19th century. Having become a picturesque area by municipal decision in 1928, it has been preserved from any new construction. The hillock's trees also protect the dwellings from possible landslides.