Everything seemed to be going so well. The engineers were ready to build the final 100 of the Metro system, between Avenida de Andalucía and the Alameda Principal, and finish a project which has been ongoing for 14 years, when they unexpectedly came across archaeological remains which meant the works had to come to a temporary halt again.
Two pieces of parallel defensive walls were revealed close to the Guadalmedina river, which archaeologists say were built during the time of the Moors. One dates back to the 12th century and the other to the 14th. The remains are located several metres below ground by the Tetuán bridge, opposite the Hacienda tax office building, and beneath a later leather tannery.
Experts believe the larger wall, which is the older of the two, is a continuation of one which was discovered during works on a previous stretch of the Metro line, near the Plaza de la Solidaridad. In medieval times it would have bordered the Attabanin district. The second stretch of wall is not as thick, and there are doubts about its use. However, as they are so close together they are both to be preserved in situ.
This will involve some complicated preservation works, but the authorisation for these was received on 10 November and Miguel Ángel García Cañizares, the head of the regional government's Public Works and Projects department, says they should be completed by the end of January.
The experience gained from similar findings during the construction of the Metro means the works can be carried out fairly quickly. Although this is an unexpected complication, García Cañizares says it will not affect the route of the last stretch of the Metro line; the ancient walls are in a stretch of tunnel between stations, so the Metro can be completed according to plan. It will, however, mean another increase in costs for the Junta de Andalucía.