The Monastery of Piedra in Zaragoza, is a site that must be seen in Spain, yes or yes. One of the best places to visit and stay for the night. It is a former monastery converted into a hotel, next to a park / garden with many waterfalls and spectacular landscapes, such as the famous horsetail waterfall.
It is located next to the city of Nuévalos and close to the famous Alhama de Aragón hot springs. It is an old Cistercian monastery from the year 1194, which has gone through many styles, from Romanesque to Gothic, and later became a ruin and an abandoned monastery with the church exposed to the open air, full of graffiti and destruction.
Today, you can stay at the monastery, which also has a restaurant and spa, and the price of admission to the park is cheaper when you stay there. Also, this place seems like Rinvendell, or even Narnia, from how fantastic it is.