How to expand subway and urban railway networks: light rail extensions in Madrid, Spain Oña López, Juan José De Calvo Poyo, Francisco Javier Garach, Laura Oña López, Rocío de López Maldonado, Griselda Light Rail LRT (Light Rail Transit) Madrid Transit system Funding Concessions Residential areas of detached houses were built in north and east Madrid, Spain, during the last decade of the 20th century. Because the popula- tion density in those areas is low, implementing an efficient transport system is complicated. In south Madrid in the 1960s, however, huge commuter towns developed. Some of them were linked to a suburban network at some point, whereas others were far away. The Madrid region promoted the construction of several light rail lines to resolve this issue. The lines function as extensions to the existing rail network (subway or suburban trains). The determining factors that enabled these lines to be implemented and operated successfully are analyzed. The recommen- dations for implementing a light rail transit system, on the basis of that analysis, are: (a) the lines should not be very long; (b) they should have a segregated right-of-way; (c) the quality of service should be good; and (d) they should be coordinated with other modes of transport. Apart from public funding, they could be funded by additional resources col- lected from property tax and the concessionaire company (private fund- ing). A concessionaire consortium may comprise construction companies, transport operators, financial institutions, rolling stock manufacturers, and consultancies. Finally, the concession should be granted for a 30- to 40-year period so that private stakeholders can recover their investment. 2013-04-08T09:17:26Z 2013-04-08T09:17:26Z 2010 journal article de Oña, J. et al. How to expand subway and urban railway networks: light rail extensions in Madrid, Spain. Transportation Research Record: Journal of the Transportation Research Board, 2146: 10–17 (2010). [http://hdl.handle.net/10481/24402] 0361-1981 doi: 10.3141/2146-02 http://hdl.handle.net/10481/24402 eng http://dx.doi.org/10.3141/2146-02 open access Transportation Research Board of the National Academies