The La Marchenilla juvenile detention center project was carried out by Exeteco in Algeciras, Spain. The facility was designed by Exeteco in collaboration with the local government and funded by the autonomous community of Andalucía. The facilities were built in two separate phases between 2003 and 2005.

On completion of the design, Exeteco realized the entire construction of the center as well as the main entrances, carpark, and 500-metre access road. The company also installed all the requisite security systems, including perimeter security with fences, presence and motion detectors, and security lights. Finally, Exeteco managed the installation of plumbing and low- and medium-voltage electrics, and connection of the center with the mains water supply.

La Marchenilla I and II are high-security units for high-risk young offenders. They have a combined 3,500 m² built area divided into modular units with space for 200 inmates in individual cells.

The detention center houses a therapeutic treatment center for young people with mental health issues – a pioneering initiative in Spain run by the autonomous community of Andalucía. It also has sporting facilities including an open-air pool, and workshop spaces used for training programs and rehabilitation.

La Marchenilla is run according to the principles of the 2002 Spanish child protection act.  It places great emphasis on rehabilitation and reintegration into society and offers training and schooling to inmates, as well as adapted treatment programs.

Aside from La Marchenilla, Exeteco has built nine other juvenile detention and social integration centers across Spain. These were all turnkey projects, managed from start to finish by Exeteco. In each case, the autonomous communities selected the companies to carry out the works who were in turn managed by Exeteco. The company also designed all the security technologies for each center and updated the security systems of a further two youth correctional facilities.