Home» Monastic Sites» Monaghan» Errigal Trough Monastery Errigal Trough Monastery Monaghan Early Irish Early Christian Ruins About This Site Early monastic site, Gaelic monks Historical Information Alternative Names: Airecal-muadain Other Sites in Monaghan Caldavnet Holy Well Located on a N-facing slope. A well, which is known locally as St Dympna’s Well or St Davnet’s Well, has… Learn More Camaghy,Tonaneeve Mass Rock Located in the valley of a rapid NW-SE stream, it is situated in Tonaneeve townland c. 5m from the E… Learn More Carrickmacross Monastery Early monastic site, founded before 845 Learn More Clochensis Friary Augustinian Friars Learn More