Where: 66 Royal Hospital Road, SW3 (the entrance is in Swan Walk)

What: Chelsea Physic Gardens were established in 1673 as London's first botanical garden, built to provide medical students facilities to study plants used for healing and 'for the propagation and study of new species'.

Several plant-based products have been discovered and tested here and this quiet, green spot, near the hustle of Chelsea, continues to be used for research and as an education facility. There are several climate-controlled greenhouses filled with treasures to delight and enthrall plant enthusiasts.

Nearest underground station: Sloane Square

Opening times: April to late October, noon - 5pm Wednesday and 2 - 6 p.m. Sunday. There are one or two free tours daily (times vary) and it is worth trying to time your visit to catch one if you can.

Admission charges apply: (2005) Adults: £6, Children 5 - 15: £3.50

Website: chelseaphysicgarden.co.uk