One of the most relevant buildings of the Basque Renaissance in Oñati is the Universidad Sancti Spiritus.
Its creation was the initiative of Rodrigo Mercado de Zuazola and its construction started in 1450. Mercado de Zuazola introduced Humanist ideas into the region and brought about the consolidation of the 16th century artistic trend: the Renaissance.
The alto relievos on the façade in Plateresque style are achieved with great skill. The typically renaissance patio, the chapel to the Pieta and the wooden vaulted ceiling in Mudejar style of the staircase are the highpoints of the interior.
Also from the beginning of the 16th century, and instigated by Juan Lopez de Lazarraga and his wife Juana de Gamboa, is the Convent de las Claras Franciscanas de Bidaurreta, the first nunnery founded in Guipuzcoa.
The Tower House of Zubiarre, situated at number 1 Calle Arantzazu, is another important building. It blends medieval elements with others from the 16th century. Without a doubt this is a reflection of a time when the great lords were the dominant force in the area.
The hamlets of Oñati contain some splendid architectural treasures and you are invited to discover some where the 16th century heritage can be best appreciated. In Torreauzo is the Tower House of Garibai, with its square and imposing structure and impressive watchtowers giving a finishing touch to the corners.
In the hamlet of Antsolopetegi it is possible to follow the steps of San Francisco de Borja who lived near the shrine of Magdalena between 1551 and 1553. The chapel of San Francisco de Borja above the sacristy and part of the pallet where he used to sleep still remain intact.