The Z-class trams, built by Comeng, were introduced in 1975. One hundred Z1-class trams were built between 1975 and 1979, the first 80 or so entering service as Z-class before being modified. The design proved unpopular with passengers due to the limited number of doors and the seated conductor. Most of the Z1-class trams were withdrawn following the introduction of the C, D and E class trams; the last Z1-class withdrawn on 23 April 2016. Many were later sold at auctions, while others were donated to tram museums.