I found this very interesting article: Anchoresses: 10 facts about the Life of Solitude. Written by the same author as the novel The Anchoress. (Alright, not super happy about the term anchoress but the article is good.)
In the Middle Ages, anchoresses were usually sealed in a cell adjoining the village church to ensure that she remained safe, and so that she could hear Mass and receive the Eucharist. An anchoress freely chose to be confined in a cell so that she could pray and read, committing her life to God. Men could become anchorites similarly enclosed in a cell, but their life was not always as restricted as that of an anchoress. In some cases they could leave to travel, and some were priests who chose to be enclosed, but would leave their cell to celebrate Mass in the church.