The six-day event has been organised by the Sherlock Holmes Society of London.

It comprises a packed programme of high-profile activities. Highlights include an opening night reception at the Tower of London, tea at the House of Lords and a Victorian music hall show at the West End's Players Theatre.

But the focal point of the festivities is Thursday's long-awaited unveiling of the capital's first statue in memory of its celebrated detective.

Baker Street station: Holmes lived at 221B Baker Street

The arrival of the nine-foot-high bronze statue - from British sculptor John Doubleday - outside Baker Street underground station marks the fulfilment of a dream for the society.

Its 1,000-plus members worldwide are devoted to the study of the life and work of Holmes, and side-kick Dr Watson, and have long campaigned for such a landmark.

After its unveiling in the street where Holmes supposedly lived, the statue will be dedicated to the people of Westminster in a colourful ceremony on Saturday.

The city's Deputy Lord Mayor will accept the monument after watching a parade of society members dressed as characters from the Holmes mysteries.

This is the first time the society has put on a festival for its hero, although it has a year-round programme of individual events.

Interest among members has been huge, with many coming from the USA, Japan, Canada and Australia to take part.

A scene from the 1942 Holmes film The Secret Weapon

Other treats lined-up for Holmes devotees this week include a film evening of rare documentary footage from the 1890s, to bring to life the world of the detective.

There will be a gala performance of the one-man play Sherlock Holmes ... The Last Act, starring Roger Llewellyn, at the Cockpit Theatre.

Distinguished Holmesian speakers from around the world will also host a symposium on the iconography of Holmes and his role as an ambassador for London.

The Return of Sherlock Holmes Festival runs from 21 to 26 September.