Park Square is one of the largest of London's private squares, designed and laid out by John Nash. Two magnificent plane trees dominate Park Crescent, said to have been planted in 1817 to commemorate the allied victory at Waterloo two years earlier. Other trees of note include a tulip tree (Liriodendron tulipifera) and weeping silver lime (Tilia tomentosa 'Petiolaris'). A historically unique feature of the garden is the Nursemaids' Tunnel, an early pedestrian underpass connecting Park Square to Park Crescent. The gardens retain most of their original Nash layout with and have been managed continuously since 1824 by the Crown Estate Paving Commission.