The name Doolin comes from "Dubh Linn" or black lake, which is also by coincidence the old Irish name for Dublin, the capital city of Ireland. It is said that the black lake was located on the site of what is today O'Connors Farmhouse B&B and Campsite. This in turn is located close to the ruins of Doolin House, which was the residence of the McNamara family for many years. Doolin House itself was burned by the British forces in retaliation for shooting of the High Sheriff of Clare, H. Valentine McNamara.

Historically Doolin was really the parish of Killilagh (also spelt Killeilagh) or the ancient territory of Tuath Clae, which at that time belonged to a branch of the O'Brien family and was named after their lands which were called Glae or Clae. Tuath Clae can then be translated as 'the lands or country side of Clae'. The main church in Doolin is to this day known as Tuath Clae church.

Killilagh itself was divided into 46 townlands. There still exists today the remains of Killilagh church and graveyard, which is located Northwest of McDermotts pub on a narrow road that leads towards the sea. There are two possible explanations for the name Killilagh, firstly is that it comes from Saint Feile or "Cill Fhaile" and secondly from "Cill Ailleach" or the church of the cliffs. An interesting feature of this church is the empty McNamara tomb, which had the unusual distinction of being used as a temporary jail during the "troubles".

There is at least one other church of note in Doolin. Toomullin Church. This is located some distance behind McDermotts Pub close to the river Aille. This church dates back to the fifteenth century. Unfortunately other interesting features in Toomullin such as the well of St. Brecan and the tomb of Conor McClancy were ploughed into the ground years ago. A fine house, Toomullin House, also stood here. This was also knocked down to make way for the phosphate mining activities, which took place here in the 1940s.