The National Trust, which owns 207 houses and 233 gardens and parks, guided nearly 11 million visitors through those historic doors in 1994, aided by 29,000 volunteer wardens who work for little more than love of the buildings.

The Historic Houses Association - which has 1,400 members, 550 of which open at some time during the year and include such famous names as Blenheim, Chatsworth and Hever - saw a 3 per cent increase in visiting numbers last year to nearly 8 million.