The London Coliseum is the largest theatre in London, seating some 2,500 people.   Situated in St Martin's Lane no more than 100 metres from Trafalgar Square, it is the work of the prolific late Victorian/early Edwardian theatre architect, Frank Matcham.   Since the late 1960's, it has been the home of the English National Opera.   The season is long, usually starting in September and running through until June.   All performances are sung in English.   At other times, it is a receiving house accommodating touring ballet and opera companies.