The staging of the Olympic and Paralympic Games led to some of London’s tourist attractions having “one of the worst trading periods in living memory”.

Some London attractions saw 60 per cent few visitors during the Games, the Association of Leading Visitor Attractions (Alva) said, while the capital’s garden and heritage spots were also badly hit by the adverse weather, and the amount people spent while visiting attractions also decreased.

London Zoo, the Tower of London and Kew Gardens were among the places that saw a decline in visitors this summer.

Overall, Alva member sites in London saw an average decrease in visitor numbers from May to August compared with the same period last year.

Garden and leisure sites in the capital received 21.3 per cent fewer visitors this summer, the capital’s heritage and cathedral sector was down 20.3 per cent and the museum and galleries sector fell 13.1 per cent.

Visitor numbers to Alva member sites also fell in the rest of England and in Scotland, but not as much as in London.

Bernard Donoghue, chief executive of Alva, said: “These figures from our 43 members, who manage nearly 2,000 tourist sites and welcome over 100million domestic and overseas visitors each year, are definitely sobering reading and show that the summer of 2012 has been a difficult time financially for our most popular and best-loved visitor attractions.

“It is our belief that for gardens and outdoor attractions across the UK, the appalling weather during much of the year has led to one of the worst trading periods since 2001 - the year of a foot-and-mouth disease outbreak.

“For London attractions, the Olympic period was one of their worst trading periods in living memory and for visitor attractions, the summer is their equivalent of retailers’ Christmas. Once lost, the business can’t be won back.

“Alva has always taken the long-term view that the economic benefits for tourism of hosting the Olympic and Paralympic Games would be long term rather than short term.

“We are working with the local and national tourist boards and others to turn the millions of Olympic TV viewers who loved how Britain looked into visitors who will come here in the next months and years.”