On which date was the British TV series "The Avengers" first shown?

"The Avengers" is a British espionage television series, created in 1961, that ran for 161 episodes until 1969. It initially focused on David Keel (Ian Hendry), aided by John Steed (Patrick Macnee). Hendry left after the first series; Steed then became the main character, partnered with a succession of assistants. His most famous assistants were intelligent, stylish and assertive women: Cathy Gale (Honor Blackman), Emma Peel (Diana Rigg), and Tara King (Linda Thorson).

The pilot episode, "Hot Snow", aired on 7 January 1961. Only about 20 minutes, the first of three acts, remain. The episode was directed by Don Leaver and generally acknowledged to have been written by Ray Rigby, but Brian Clemens claimed to have written it.

By 1969, The Avengers was shown in more than 90 countries. ITV produced a sequel series, The New Avengers (1976–1977), with Patrick Macnee returning as John Steed, and two new partners: Mike Gambit (Gareth Hunt), a top agent, crack marksman and trained martial artist, and Purdey (Joanna Lumley), a former trainee with The Royal Ballet.