Santa Teresa is the name of a small area in Ávila, a Spanish city, and home of the Convent (Convento de Santa Teresa) where Number Seven and her Cêpan Adelina lived for many years as Adelina had lost faith in the rise of Lorien and found a new faith. 

It is situated near the mountains, where Seven found solace in being alone.

Santa Teresa and the convent is destroyed by the Mogadorians as they attempted to capture/kill Number Seven. The loss of the town and the high amount of deaths, including Adelina and Héctor, that occured as a result of the attack is something that Marina holds herself responsible for.
Avila Santa Teresa

Convento de Santa Teresa, Ávila, Spain.