Light Rail Transport (L.R.T.)
LRT systems run mostly in reserved lanes (with short underground sections), using tram-like rolling stock.
This definition includes a wide range of applications, from tramway to light metros.
It appears correct to intend as properly said LRT systems those mass rapid transit which couldn't be classified into classical trams or metros types and, in comparison to heavy railways, have lighter infrastructures, shorter vehicles and higher frequencies; all these features allow significant cost reductions without penalizing system capacity and facilitating the urban insertion of the infrastructure (expecially when the existing urban texture is rich of archeological and architectonics elements).
In many cases LRT systems consist in local or regional railway lines brought into the urban area, creating urban sections with lower distance between the stops and powered frequencies.
Track is protected and segregated from road traffic in crossroads by traffic lights priority or level crossings.
"Premetro" systems can also be considered among LRT; they generally have a ground level (or, seldom, o on viaduct) track in suburban areas and underground central sections; in many cases underground central segments are utilized in a first phase by existing tram-like rolling stock (v. Bruxelles, Stuttgard), while in further phases metro-like rolling stock can be adopted.
Links to manifacturer sites