{{Short description|Type of tramway or light rail}} {{distinguish|Light metro|Tram-train}}{{use dmy dates|date=December 2022}} [[File:Bruxelles - Brussel - Parvis de Saint-Gilles - Sint-Gillis Voorplein (12038666124).jpg|thumb|upright=1.1|Trams at Saint-Gilles/Sint-Gillis station with partially low platforms in Brussels.]] [[File:Stadtbahn Duisburg Hauptbahnhof 1905300952.jpg|thumb|upright=1.1|Low platform section for trams at Duisburg Hauptbahnhof Stadtbahn station.]] thumb|upright=1.1|Low platform station for trams in Vienna during transformation. A third rail and emergency stairs from the future high platform have already been installed. [[File:Stazione pantano (cropped).jpg|thumb|upright=1.1|Pantano station before conversion.]]
'''Premetro''' (or '''pre-metro''') is a type of light rail designed for eventual conversion to a full rapid transit (also known as a metro).<ref name="DLC&C">{{cite book |last1=De Leuw, Cather & Company |url=https://books.google.com/books?id=s_FyYpNHB0UC |title=Light Rail Transit: A State of the Art Review, Executive Summary |date=1976 |page=47 |quote=This step-by-step planning approach to building rail rapid transit is known as pre-metro, implying the intention to ultimately construct a fully grade separated route to be used by rail rapid transit or ''metro'' trains. |access-date=30 August 2023}}</ref><ref name="UTST2007">{{cite book |last1=Vuchic |first1=Vukan R. |title=Urban Transit Systems and Technology |date=16 February 2007 |publisher=John Wiley & Sons |isbn=978-0-471-75823-5 |page=580 |url=https://books.google.com/books?id=zFby0C3ohwQC |access-date=19 August 2025 |language=en}}</ref><ref name="TRB165">{{cite book |last1=Program |first1=Transit Cooperative Research |url=https://books.google.com/books?id=6c_BngEACAAJ |title=Transit Capacity and Quality of Service Manual |date=2013 |publisher=Transportation Research Board |isbn=978-0-309-28344-1 |page=53 |language=en |chapter=11 Glossary and symbols |quote=pre-metro — a light rail transit system designed with provisions for easy conversion to heavy rail (rail rapid transit).}}</ref> These systems typically include infrastructure such as tunnels, viaducts, and dedicated rights-of-way to separate them from other traffic, built to metro standards with wider curves and gentler gradients than conventional light rail lines.<ref>{{cite book |last1=Mattila |first1=Matti |url=https://books.google.com/books?id=1Gy_r1gCEYUC&pg=PA19 |title=Wizzit Magazine 3/2011 |date=5 August 2012 |publisher=Annorlunda Mediatuotanto Oy |isbn=978-1-4478-2842-6 |page=19 |quote=Premetros also allow a gradual upgrade of existing tramways to rapid transit, thus spreading the investments costs over time. |access-date=9 August 2024}}</ref><ref name="SMH">{{cite news |author=John Hoyle |date=16 May 1975 |title=Letters to the editor -- The tram is the answer |url=https://news.google.com/newspapers?id=RfpjAAAAIBAJ&pg=5235%2C5030573 |access-date=2014-01-13 |newspaper=Sydney Morning Herald |quote=Cities such as Frankfurt and Cologne in West Germany have further developed their tramway system by introducing a concept known as "premetro." In this system trams or light rail vehicles make extensive use of tunnels, reserve track and by utilizing folding steps these vehicles can operate through high or low stopping places.}}</ref><ref>{{cite book |last1=Jenkin |first1=P. |url=https://books.google.com/books?id=Yt1cqH7u0UkC&pg=PA10 |title=Urban Railways and the Civil Engineer |date=1988 |publisher=Thomas Telford |isbn=978-0-7277-1337-7 |quote=Pre-Metro is an extreme case of light rail, on segregated right of way, and designed to upgrading to metro when passenger demand increases sufficiently. |access-date=9 August 2024}}</ref> However, they often include sections without full segregation, limiting immediate conversion. Premetros are usually operated with light rail vehicles or trams until an upgrade is implemented.
Several cities have referred to portions of their light rail networks as a pre-metro, including Brussels<ref>{{Cite web |title=History - STIB - MIVB |url=https://www.stib-mivb.be/about-stib-mivb/history |access-date=2025-04-06 |website=www.stib-mivb.be}}</ref><ref>{{Cite web |last=Times |first=The Brussels |title=Schaerbeek pre-metro station gets facelift – others to follow in 2025 |url=https://www.brusselstimes.com/1392399/schaerbeek-pre-metro-station-gets-facelift-others-to-follow-in-2025 |access-date=2025-04-06 |website=www.brusselstimes.com |language=en}}</ref> and Antwerp.<ref>{{Cite web |title=History |url=https://www.delijn.be/en/content/geschiedenis/ |access-date=2025-03-27 |website=www.delijn.be}}</ref><ref>{{Cite web |last=News |first=Flanders |date=2022-02-11 |title=Discover the plans for four new Antwerp pre-metro stations |url=https://www.vrt.be/vrtnws/en/2022/02/11/discover-the-four-new-antwerp-pre-metro-stations/ |access-date=2025-03-27 |website=vrtnws.be |language=en}}</ref> Additionally, Buenos Aires has a light rail line named Premetro,<ref>{{Cite web |title=Premetro ≫ Recorrido, estaciones, combinaciones, y horarios |url=https://subte.ar/premetro/ |access-date=2025-03-27 |website=SUBTE |language=es-AR}}</ref><ref>{{Cite web |date=2024-11-29 |title=City government expands payment options for Subte metro service |url=https://www.batimes.com.ar/news/argentina/buenos-aires-city-government-expands-payment-options-for-subte-metro-service.phtml |access-date=2025-03-27 |website=Buenos Aires Times |language=en}}</ref> however this operates as a feeder line to the metro network, and was not built with plans for conversion to full rapid transit.<ref>{{Cite web |date=2013-08-16 |title=Premetro a Puente de la Noria, en el olvido por el Metrobus del Sur |url=https://enelsubte.com/noticias/premetro-puente-la-noria-el-olvido-el-metrobus-del-sur-2781/ |access-date=2025-04-06 |website=enelSubte |language=es-AR}}</ref>
==History== An early example of was the Tremont Street subway (1897) in Boston, today part of the MBTA Green Line. This tunnel was intended solely to reduce streetcar congestion on surface streets, not for later conversion to metro service.<ref name=cudahy /> However between 1901 and 1908, two out of four tracks were used for rapid transit service including high platforms.<ref name="NYCsw">{{cite web |title=Boston Elevated Railway Company, Main Line Elevated Structure (HAER) |url=https://www.nycsubway.org/wiki/Boston_Elevated_Railway_Company,_Main_Line_Elevated_Structure_(HAER) |website=www.nycsubway.org |quote="the outer tracks of the Tremont Street Tunnel which was adapted to elevated train use in 1901 by the construction of higher platforms" |access-date=7 August 2024}}</ref> Several early streetcar tunnels, including the Steinway Tunnel and East Boston Tunnel, were later converted to metro operation. However, the small loading gauge, tight curves, and steep grades of the streetcar tunnels required shorter metro cars than otherwise desirable.<ref name=cudahy>{{cite book |title=Change at Park Street Under |last=Cudahy |first=Brian J. |year=1972 |publisher=Stephen Greene Press |isbn=0828901732 |lccn=72081531 |pages=[https://archive.org/details/changeatparkstre00cuda/page/10 10-11, 31-33] |url-access=registration |url=https://archive.org/details/changeatparkstre00cuda/page/10 }}</ref> In 1950 Stockholm converted a 1920s tram tunnel for its first rapid transit line.<ref name="LURS">{{cite book |last1=Geoffrey |first1=Skelsey |title=Brussels Metro to Grow As Pre-metro Shrinks |date=2018 |publisher=London Underground Railway Society |page=3}}</ref>
===Second generation=== The modern premetro concept {{lang|de|Stadtbahn}} began in 1960s Germany, as rising traffic congestion due to auto ownership led to the construction of new transit systems. Rather than building costly metro lines immediately, some cities built only the downtown tunnels. They could be used by existing tram lines in the short term, with the intention of full metro conversion later - hence "pre-metro".<ref name="newscientist">{{cite journal |url=https://books.google.com/books?id=xgKLfKjjft8C&pg=PA699 |author=Ian Yearsley |title=Trams are coming back |journal=New Scientist |publisher=Reed Business Information Ltd. |quote=<!-- But West Germany, like other nations, experienced a phenomenal growth in private car ownership. Traffic congestion led to plans for underground railways. --> But instead of building the entire expensive systems immediately, the Germans hit on the idea of building only the city centre tunnels at first. Intended in the long run to be extended to full undergrounds, in the short term they could be used by trams which would continue to run on the surface outside city centres. The idea spread to other European countries, especially Belgium, where it became known as pre-metro. Today Brussels, Frankfurt, Stuttgart and many other cities are filling their central business districts with construction sites to move the trains underground. |date=21 December 1972 |access-date=2014-01-14}}</ref> The idea spread to other European countries in the 1970s, especially Belgium, where such systems were explicitly named premetros.<ref name="newscientist" /> Also, one segment of Vienna's U2 metro line (Rathaus-Museumsquartier) was an underground tramway line constructed in 1966 and converted in 1980.
== Terminology == {{Original research|section|date=August 2025|reason=}} The use of tram vehicles in tunnels originated in the United States in the nineteenth century and was often called "subway–surface line". Later, in the second half of the twentieth century the term "semi-metro" was coined for tram systems with some sections in tunnels and on viaducts. Only when a semi-metro section is designed for later use of heavy rapid transit trains, it falls in the premetro category.{{Citation needed|date=August 2025}} The large scale report "Light Rail Transit: A State of the Art Review" describes on page 9 the relationship of premetro systems to broader terms as follows: {{Quote frame|Certain design features distinguish these systems from semi-metro or conventional light rail transit systems<ref name="DLC&C" />|align=center |width=55%}} The same distinction is made in glossaries.<ref name="TRB165" /><ref>{{cite web |date=8 October 2009 |title=PREMETRO [1 record] |url=https://www.btb.termiumplus.gc.ca/tpv2alpha/alpha-eng.html?lang=eng&srchtxt=PREMETRO&i=1&index=ent |access-date=23 July 2024 |publisher=TERMIUM Plus® |language=fr |quote=Un semi-métro peut constituer une étape intermédiaire vers la constitution d'un véritable métro lorsqu'il est envisagé d'étendre par phases successives le site propre intégral à la totalité de la ligne ou du réseau. Les ouvrages sont alors dimensionnés au gabarit du futur métro et on parle du pré-métro.}}</ref> During the period when tram vehicles are used, the specific line falls into the light rail category.<ref>{{cite book |last1=Transportation Research Board National Research Council |url=https://trid.trb.org/view/297446 |title=Urban Public Transportation Glossary |date=1989 |quote=pre-metro: a light rail transit system designed with provisions for easy conversion to rail rapid transit |access-date=16 February 2023}}</ref><ref name="UTS&T">{{cite book |last1=Vuchic |first1=Vukan R. |url=https://onlinelibrary.wiley.com/doi/epdf/10.1002/9780470168066.fmatter |title=Urban transit systems and technology |date=2007 |publisher=J. Wiley & Sons |isbn=9780471758235 |location=Hoboken, N.J |page=580 |doi=10.1002/9780470168066.fmatter |quote=PREMETRO—An LRT system designed with provisions for easy conversion into RRT (metro). |access-date=7 October 2023}}</ref>
== Examples == {{Main|List of premetro systems}} === Previously converted lines === * Line 2 (Rio de Janeiro) in Brazil<ref>{{cite book |last1=Araujo |first1=Ricardo Melo |title=Plano conceitual de transporte de passageiros sobre trilhos na Região Metropolitana de Curitiba |date=December 2017 |location=Curitiba |page=36 |url=https://www.researchgate.net/publication/325696240 |language=pt |access-date=30 October 2024}}</ref> * Two stations of the Rome–Fiuggi–Alatri–Frosinone railway were converted to metro standards to become part of the Rome Line C. * Vienna premetro in Austria
=== Lines being converted === * Brussels Pre-metro<ref>{{cite web|title=Une station fantôme au secours du futur Métro Nord de la STIB|url=http://www.rtbf.be/info/regions/detail_une-station-fantome-au-secours-du-futur-metro-nord-de-la-stib?id=8226114|author=Geoffroy Fabre|publisher=RTBF|date=2014-03-19|access-date=2014-05-09}}</ref> in Belgium === Lines without plans to be converted === * Antwerp Pre-metro<ref>{{Cite web |last= |first= |date=2022-02-11 |title=Discover the plans for four new Antwerp pre-metro stations |url=https://www.vrt.be/vrtnws/en/2022/02/11/discover-the-four-new-antwerp-pre-metro-stations/ |access-date=2025-03-27 |website=vrtnws.be |language=en}}</ref><ref name="Antwerp">{{cite web | url=http://www.urbanrail.net/eu/be/ant/antwerpen.htm | title=Antwerpen Tram & Premetro | website=UrbanRail.net | quote=Antwerpen rail network is a typical premetro network. | year = 2013| access-date=2014-01-22}}</ref> in Belgium * Kryvyi Rih Metrotram in Ukraine
==See also== * Medium-capacity rail system * Train categories in Europe
== References == {{reflist|30em}} {{Trams}}
Category:Light rail Category:Tram transport Category:Rapid transit