Guided Light Transit (GLT, ) was the name of guided bus technology and associated infrastructure designed and manufactured by Bombardier Transportation (now Alstom). It was installed in two French cities: Nancy and Caen. As of 2022, only the Nancy system is in operation, however it will be withdrawn in February 2023 and replaced by trolleybuses. The Caen system has been abandoned and now rebuilt as a conventional tramway by 2019. Both of the systems in these cities are referred to as "tramways on tyres", and in common with tram systems they use a surface guidance system and in normal operation are powered by electricity drawn from an overhead wire. However, while the vehicles are guided by a central guidance rail, they ride on rubber tyres, not on rails. There has been disagreement about whether they should be called "trams", for that reason and also because they are capable of being steered and operating independently of the guidance rail, using auxiliary diesel engines. GLT is effectively a model of guided dual-mode bus, but when GLT vehicles use a pantograph to collect current, as do those in Caen, they are not commonly considered to be trolleybuses. English transport publications generally refer to the GLT and the competing Translohr system as "rubber-tyred tramways", but rarely simply as "tramways", as they are not tramways in the conventional sense, but neither are they buses when pantograph-equipped and operating in service as designed (i.e. in electric mode). GLT was one of the few models (together with the Innovia APM) of rubber-tyred vehicles produced by Bombardier's transport division, which is otherwise focused on rail transport. Characteristics GLT and the similar Translohr are often described as the tram equivalent of rubber-tyred metro technology, but this is not strictly accurate; while the GLT follows a central rail, the rail does not support the vehicle, and the actual wheels which are as independent as those of a regular bus. The wheels of rubber-tyred metros, on the other hand, are bound and guided by their rails in the same way as are steel-wheeled trains. Unlike trams and Translohr vehicles, GLT vehicles have a steering wheel, though it is not used when following a guidance rail. On the GLT line in Nancy, more than one-third of the route has no guide rail, and steering is controlled entirely by the driver on those sections. The Nancy GLT system is operated by the Société