Barragem do Alqueva

The dam of the Alqueva Reservoir was completed in 2002. It is a reservoir on the River Guadiana on the border between Portugal and Spain. It is around 85 kilometers long and has an area of around 250 square kilometers, 187 of which are in Portugal. The lake is very rugged, so the shoreline is unusually long.

In terms of volume, it is one of the largest reservoirs in Europe.