The Sir Harold Hillier Gardens is an arboretum comprising 72 hectares (180 acres) accommodating over 42,000 trees and shrubs in about 12,000 taxa, notably a collection of oaks, camellia, magnolia and rhododendron. The Gardens are located 5 km (3 mi) northeast of the town of Romsey in Hampshire, England, and were formerly known simply as the Hillier Arboretum, founded by nurseryman Harold Hillier in June 1953 when he acquired Jermyn's House and its grounds. The Gardens were listed as Grade II on the National Register of Historic Parks and Gardens in 1997.