Series 1: 1964–1965
Series 2: 1965–1966
Series 3: 1966–1967
Series 4: 1967–1968
Series 5: 1968–1969
Series 6: 1969–1970
Series 7: 1970–1971
Series 8: 1971–1972
Series 9: 1972–1973
Series 10: 1973–1974
Series 11: 1974–1975
Series 12: 1975–1976
Series 13: 1976–1977
Series 14: 1977–1978
Series 15: 1978–1979
Series 16: 1979–1980
Series 17: 1980–1981
Series 18: 1981–1982
Series 19: 1982–1983
Series 20: 1983–1984
Series 21: 1984–1985
Series 22: 1985–1986
Series 23: 1987
Series 24: 1988
Series 25: 1988–1989
Series 26: 1990
Series 27: 1990–1991
Series 28: 1992
Series 29: 1992–1993
Series 30: 1993–1994
Series 31: 1994–1995
Series 32: 1995–1996
Series 33: 1996–1997
Series 34: 1997–1998
Series 35: 1998–1999
Series 36: 1999–2000
Series 37: 2000–2001
Series 38: 2001–2002
Series 39: 2002–2003
Horizon Revisited was broadcast onSeries 40: 2003–2004
Series 41: 2004–2005
Series 42: 2005–2006
Series 43: 2006–2007
Series 44: 2007–2008
Series 45: 2008–2009
Series 46: 2009–2010
Series 47: 2010–2011
Series 48: 2011–2012
Series 49: 2012–2013
Series 50: 2013–2014
Series 51: 2014–2015
Series 52: 2016
Series 53: 2017
Series 54: 2018
Series 55: 2019
Series 56: 2020
Series 57: 2021
Series 58: 2022
References
;General