The Magdalena hermitage occupies a mountain of the same name, which rises above Castellón. The hermitage originates from the 13th century, following the Christian conquest of 1233. The first documentary reference to a penitential procession that reached the Castell Vell hermitage dates from 1375, when the city was suffering from a plague epidemic. Nothing remains of that primitive hermitage, not even the memory of its exact location.

Construction of the current hermitage began in 1451, undertaken by a friar from the Monastery of Santes Creus popularly known as the frare barbut, whose real name was Antoni. He made use of an ancient large-scale cistern excavated into the rock and built a structure comprising two parallel naves separated by rudimentary arches, covered with a barrel vault. The entrance portico, with a round arch of regular voussoirs, was added in 1455, and the chapel was built in 1456. Between that date and 1590, various renovation and extension works took place: the main altar was provided with a wooden altarpiece and the stables were rebuilt to serve pilgrims. The final form that the complex presents today—hermitage-hospice with an adjoining tower serving as a bell tower—was established in 1758 by Vicente Pellicer.

As a destination for supplications and pilgrimages during the Middle Ages and in later times, the hermitage had kitchens, a dining room, cisterns and lodgings, which the Municipal Council—owner of the Santa Magdalena house and hermitage—periodically reconstructed and reformed. Beside the hermitage are the remains of the castle, of which a section of fortification wall and two lime mortar walls are preserved. Juan Bautista Balbás, in his Libro de la Provincia de Castellón from 1892, documented the discovery in the lower strata of Castell Vell of column bases, coins and Roman tombs; subsequent excavations brought to light roof tiles used in burials and fragments of sigillata pottery.

The complex was declared an Asset of Cultural Interest in 1996.