This railway line was originally built for transporting ore mined in the Sierra. Now fallen into disuse, it offers visitors an excellent chance to explore this region, allowing us to enjoy its varied scenery and leafy riverside carrs and copses. The station of the lovely mountain towns of Cazalla and Constantina is the ideal starting point for our trip. The station can be reached along the N-432 road (coming from the Province of Córdoba, in Fuente ovejuna, then continuing along the A-447 and from the province of Badajov, in Llerena, then continuing along the A-432). To the west of the station is Cazalla de la Sierra, an interesting example of local Andalusian architecture (see page 90). To the southeast of the A-455 lies Constantina, containing the park’s Information Centre. Finally, another road, the SE-168, climbs northwards alongside the railway line until reaching San Nicolás del Puerto alongside the River Huéznar. The route passes through a series of typical courtyard farms “cortijos” until reaching the town of San Nicolásdel Puerto. From here the railway turns south again towards the village of Cerro del Hierro, passing through a singular karstic landscape.