ULF (Ultra Low Floor) is the tram with the lowest entrance height in the world - so low that no platform is needed. This means optimal boarding convenience, which is a particular benefit to the elderly, wheelchair users, and parents with strollers - as is the flat floor throughout the coach. The large number of doors allows fast passenger turnaround - and at travel speeds of up to 70 km/h, it is easily possible to achieve shorter scheduling intervals. The radially-adjustable individual wheel bogies ensure optimum running characteristics.
In order to modernize the tram fleet in Vienna, the local operator Wiener Linien purchased 150 ULF trams in the 1990s. Thanks to the success of their operation and the high degree of acceptance by passengers, another 150 ULFs were ordered in 2004. Continuous production of ULFs allows you to purchase even short production runs at low cost. More information and history on:http://public-transport.net/bim/Ulf.htm