El Fadrí is a Gothic bell tower located in Plaza Mayor in Castellón de la Plana. Its name, which in Valencian means 'the bachelor', refers precisely to its status as a freestanding tower: unlike most bell towers, it is not attached to any church, but stands independently next to the co-cathedral of Santa María.

Construction of the tower extended over more than a century, from the late fourteenth century to the sixteenth century, which explains the coexistence of different styles and construction phases in its structure. It reaches a height of 58 metres and its floor plan is octagonal, a feature that distinguishes it from the more common prismatic bell towers in the region.

El Fadrí is municipally owned and forms part of the monumental complex of Plaza Mayor, alongside the co-cathedral of Santa María and the former Town Hall. It is managed by the Museu de Castelló (MUCC), which allows access to the interior and ascent to its various floors.

Considered the quintessential symbol of the city, the tower appears in the coat of arms and official iconography of Castellón de la Plana. Its image is omnipresent in local culture, and there is even a festive distinction called 'Fadrí d'Or' that the Town Hall awards to notable individuals and institutions during the Magdalena festivities.

From the top of the tower, there is a complete panoramic view over the city and the Plain of Castellón to the Mediterranean Sea. Its state of conservation is good and it is one of the most visited monuments in the province of Castellón.