Original models of the planned Tren Urbano rolling stock.
The first of the new trains began testing in December 1999.
Tracklaying in progress opposite the maintenance depot at Las Lomas.
Part of the test track under construction.
Building work underway at Martinez Nadal station, close to the site of the main maintenance depot.
Information, control and signalling systems will be integrated in a system installed by Matra Transportation International.

By the early years of the new millennium, the Puerto Rican capital of San Juan will have the first rapid transit system in the Caribbean. Known as Tren Urbano, the route will be a double-track, 10.6-mile line, serving 14 new stations, running from Bayamon to Santurce.

The inspiration for the project came from the growing number of American cities which gained new rapid transit systems during the 1980s and 1990s. Studies demonstrated a clear need for a new urban transit system, but that conventional light rail would be unlikely to be able to cater for the demand which could be generated.

The project

Siemens has a concession to design and build the line and its rolling stock, and to operate it for the first five years. It won a contract which was a ‘first’ for North America in the scope of the work which is involved, and which was awarded in July 1996.

The first phase comprises a single 17.2km route linking Bayamon and Santurce, near old San Juan. The line will initially operate for 20 hours each day, with a minimum headway of four minutes.


The line is being built with total grade separation and high-level platforms. Of the 16 stations, ten will be elevated, four at grade or in open cuttings, and two underground. A maintenance depot and operations control centre is being provided halfway along the route, at Las Lomas.

Electrification is at 750V DC through a third rail, with power coming from five new substations, feeding ten further stations supplying traction power, and 17 serving the stations and depot.

A test track section has been built, on which the new trains will undergo commissioning. British company DMJM is acting as consultants for the project management, conceptual design, system and station design, and construction supervision.

Rolling stock

Services will be operated by a fleet of 74 stainless steel metro cars, equipped with three-phase drives. Each vehicle will carry 72 seated and 108 standing passengers. They will run as permanently-coupled pairs, and up to three pairs will run together at any time.

The trains’ top speed will be 100km/h (60mph), with power provided by AC traction motors, chosen over DC as they contain fewer moving parts and require less maintenance. The trains share many characteristics with the stock built by Siemens for Boston MBTA’s Red Line route.

Air-conditioning systems, have, however, been specially designed to cope with the hot, muggy conditions which are the norm in San Juan.

Signalling and communications

The line will be governed by full automatic train operation, allowing possible driverless operation, although this is unlikely to be implemented for security reasons. Substations providing the power will be remotely controlled from the Las Lomas operational control centre.

Siemens subsidiary Matra Transport International is providing the transmission-based train control system, derived from the digital technology used on the Paris Meteor light rail system. Signalling sections are divided into fixed blocks, each sub-divided into station areas, and a speed measurement system that monitors trains’ progress and can automatically intervene if speeds vary substantially from those permitted.

The future

The system is seen as a trailblazer for urban transit in South America, where population growth is demanding new solutions to mobility problems. The Cuban capital of Havana is watching Tren Urbano’s progress particularly keenly, and may follow suit with a similar installation if it proves successful.

Extensions are being actively considered, with an extra 2km addition to Line one to Minilas the subject of environmental studies.

A second 12.2km phase could run east from Rio Piedras to a park and ride facility at Carolina, while the international airport at Isla Verde, Old San Juan, and the southern municipality of Caguas are also projected to be linked into the system.