During the recent years the use of the tram has been gaining ground , and has become the basic means of mass transportation in many capitals of the world. It is environment friendly and convenient to the citizen, while it adds a different perspective to the streets it goes through. Τhe tram has become a symbol of civil quality of modern capitals.

In many cities it has been re-installed, in others the network was modernized and expanded and in some it was re-designed from scratch, according to the needs of the citizens. The Athens tram belongs to the “new tram “ category, same as the one in Paris, Brussels, Strasbourg, Lyon, Montpelier, Grenoble, Hanover, Stuttgart, Cologne and Manchester from a technological and morphological characteristics point of view. Cities with population equivalent to Athens also have extensive such tram networks: Melbourne has a tram network of 240 kilometers and 28 routes, Berlin a network of 182 kilometers and 28 routes, St Petersburg one of 678 kilometers and 65 routes, Milan one of 168 kilometers and 16 routes. There are also cities with population less than the population of Athens with extensive tram networks: Vienna has a network of 183 kilometers with 33 routes, Amsterdam has a network of 138 kilometers and 17 routes, Brussels, one of 133 kilometers on 15 routes and Prague, 494 kilometers on 31 routes. In more than 400 cities all over the world there are tram networks of which 72 are of recent construction from scratch. It is the one mean of mass transportation which is growing in the most dynamic manner. At this moment there are tram networks under construction in 27 cities, while construction is planned in 72 more, all over the world.

The cities which recently reinstated, modernized or expanded their tram network include Hanover, Bern, Basil, Budapest, Grenoble, Stuttgart, Bonn, Zurich, Manchester, Dusseldorf, Los Angeles, Boston, San Francisco, Sacramento, Buenos Ayres, Hong Kong, Valencia, Torino, Strasburg, Istanbul, Ikonio, Buffalo, Portland and San Diego.
The tram is a (today exclusively electric) light urban railway, which primarily moves on the surface and not underground along, main traffic arteries, either on the surface together with the rest of the vehicles, or on the sidewalk, or in a separate, dedicated lane, guarded or open, on the edge or in the middle of the road (along the central isle). An exclusively dedicated lane may also be used, railway type, completely independent of the main traffic routes, on the surface, on an overpass or even underground. The traditional tram offered minimum comfort, interfered with traffic, had no right of way in the intersections was of low passenger capacity and there were no vibration and noise reduction provisions. These were some of the reasons for which during the 50’s and 60’s it was considered as an old fashioned mean of transportation and was dismantled and removed from many cities, in particular of the Western world.

The standard and traditional advantages, being an electrically powered mean of constant course, in conjunction with the increase of traffic and pollution, the  saturation of the urban road infrastructures and the realization of the high costs involved in the construction of the conventional subways or the administration of large scale bus fleets, as well as the slow speeds of the cable trolleys under the current traffic situations, led in reconsidering the role of the tram. In this manner a series of technological and operational innovations were applied for the modernization, upgrade and evolution of the traditional tram, leading to the development of the modern one as well as the light metropolitan subway better known today as the “Light Rail Transit” or LRT.