Rathcroghan

Rathcroghan (Irish: Ráth Cruachan, meaning 'fort of Cruachan') is a complex of archaeological sites near Tulsk in County Roscommon, Ireland. It is identified as the site of Cruachan, the traditional capital of the Connachta, the prehistoric and early historic rulers of the western territory. The Rathcroghan Complex (Crúachan Aí) is an archaeological landscape with many references found in early Irish medieval manuscripts.

Located on the plains of Connacht (Mag nAí/Machaire Connacht), Rathcroghan is one of the six Royal sites of Ireland. The landscape extends over 6 square kilometres (2.3 sq mi) and consists of over 240 archaeological sites, 60 of which are protected national monuments.

The monuments range from the Neolithic (4000–2500 BC), the Bronze (2500–500 BC) and Iron Ages (500 BC–400 AD), to the medieval period. These monuments include burial mounds, ringforts and medieval field boundaries amongst others. The most prominent of these are the multi-period Rathcroghan Mound, the Oweynagat cave, the Mucklaghs (a set of linear earthworks), and the Carnfree medieval complex.

There are many historic references to Rathcroghan (Ráth Crúachan) recorded in early medieval manuscripts, including the 12th-century Lebor na hUidre. Rathcroghan is recorded as the location of one of the great fairs of Ireland, as well as being one of the island's three great heathen cemeteries. It is also the location for the beginning and end of the Táin Bó Cúailnge and the royal seat of Medb, a mythical queen of Connacht.

Rathcroghan is said to provide entrance to the Otherworld, described in the medieval period as "Ireland's Gate to Hell" (not to be confused with St Patrick's Purgatory), via Oweynagat (the Cave of the Cats). The cave has associations with the pagan festival of Samhain as well as being described as the dwelling of Morrígan, a mythical figure in early medieval Irish literature.

According to National Geographic, the site may be "Europe's largest unexcavated royal complex". It is designated a Royal Site of Ireland by the Irish government. Ireland applied for UNESCO World Heritage status for the site in 2021.

According to a Dindshenchas poem, Cruachan was named after Crochen, the handmaid of Étaín, a sídhe maiden reborn as a mortal. When Étaín is brought back to the Otherworld by her original sídhe lover Midir, Crochen accompanies them and on their way to Midir's underground palace they spend some time in a mound known as Síd Sinche.

Crochen is so impressed by this síd (fairy mound) that she asks Midir if this is his palace. Because of her loyalty to Étaín and her respect to this dwelling, Midir gives it to her and names it in her honour before bringing Étaín to his palace at Bri Leith. At the end of the poem Crochen is mentioned as the mother of Medb.