The catholicon of the old Monastery of St. Golgotha and its chapels are just south of the main altar of the Catholicon. Leandro Alberti wrote a defense of the "Catholicon" in response to these attacks. The first Breton dictionary, the "Catholicon", was also the first French dictionary. In 1464 the Catholicon, a Breton-Latin-French dictionary by Jehan Lagadeuc, was published. He built a surrounding wall, many cells, as well as the monastery's catholicon. It is a semi-detached building in the west wing, across from the catholicon.