The Museum Gardens The Museum Gardens are one of York's most attractive parks and extend from the back of the King's Manor down to the banks of the river. Central to the Gardens is the classical building which houses the Yorkshire Museum. Entrances to the Gardens are on Museum Street, from Marygate, and from the riverside walk. Also standing in the grounds is the York Observatory, which has been used for more than 150 years and houses the 1850 Thomas Cooke telescope. At the entrance to the gardens from Museum Street are the ruins of St Leonard' Hospital, as well as the remains of The Roman Legionary Fortress Wall, surviving up to parapet level, and the west corner of the Roman Fortress, known as the Multangular Tower.