Dan-Air Flight 1903 was a de Havilland Comet 4 aircraft operated by Dan Air Services Limited that, on Friday, 3 July 1970, crashed into the wooded slopes of the Serralada del Montseny near Arbúcies, in the Province of Girona of Catalonia, Spain. The flight was on a non-scheduled international passenger service from Manchester to Barcelona. British tour operator Clarksons Holidays had contracted the aircraft to carry a group of holidaymakers who had booked an all-inclusive package holiday with the operator. The crash resulted in the aircraft's destruction and the deaths of all 112 on board. It was the deadliest aviation accident in 1970, and remains the deadliest aviation accident involving the De Havilland Comet.