Castlebaldwin or Bellanagarrigeeny is a townland

Townland

A townland or bally is a small geographical division of land used in Ireland. The townland system is of Gaelic origin—most townlands are believed to pre-date the Norman invasion and most have names derived from the Irish language...

 and village in County Sligo, Ireland

Republic of Ireland

Ireland , described as the Republic of Ireland , is a sovereign state in Europe occupying approximately five-sixths of the island of the same name. Its capital is Dublin. Ireland, which had a population of 4.58 million in 2011, is a constitutional republic governed as a parliamentary democracy,...

.

The castle outside the village of Castlebaldwin is a fortified 17th century house (Duchas reference SL034-185--- Grid reference G:75686:14470) rather than a medieval castle, with gun slits in the walls and a machicolation

Machicolation

A machicolation is a floor opening between the supporting corbels of a battlement, through which stones, or other objects, could be dropped on attackers at the base of a defensive wall. The design was developed in the Middle Ages when the Norman crusaders returned. A machicolated battlement...

 over the door. The walls of the castle are made from stones taken from a nunery that was near the village. To hold the stones together blood from animals was mixed to sand to form mortar to help the stones stick. Castlebaldwin is situated near the Carrowkeel Passage Tombs

Carrowkeel Megalithic Cemetery

Carrowkeel is a Neolithic passage tomb cemetery in the south of County Sligo, near Boyle, County Roscommon. An Cheathrú Chaol in Irish means 'the Narrow Quarter'. Circumstantial Carbon 14 dating places the tombs at between 5400 and 5100 years old, so that they predate the Pyramids on Egypt's Giza...

which are some of the oldest tombs in Europe.