Double-decker buses in Portugal were introduced during the 1950s when buses in general started to be driven in the main cities of the country, such as Lisbon, Porto, Coimbra and Setúbal. The type of buses were built by AEC (Regent) and later, vehicles produced by Daimler (Fleetline) and Leyland (Atlantean) with Portuguese bodywork or original. there was also one Leyland Olympian as a demostrational bus for Lisbon. In Porto, there were double-decker trolleybuses, produced by Lancia and with Dalfa bodywork, putted in circulation in the middle 1960s until middle 1990s. Double-decker buses were not a common vehicle for normal service, but for sightseeing purposes, most commonly Portuguese produced vehicles, including rebodies from regular service buses (for example, the Volvo B10R from Carristur), aswell as ones from former companies, such as the MAN SD202 from BVG Berlin, many of them still in circulation. This situation with no double-decker buses on regular service lasted until 2011, when STCP acquired fifteen double-decker buses, with the model MAN A39 (same ones as in Berlin). They were presented as an event made by the company, named "Duplex Tour" at the 26th of February, 2011 and put them into normal service on the 28th of the same month and year. These buses can be found normally on bus line 500.