Dún Ailinne, located in Knockaulin Townland, near Kilcullen, County Kildare, was one of the preeminent royal sites of pre-Christian Ireland—the Leinster equivalent to Emhain Macha in Ulster, Cruachain in Connacht, and Tara in Mide. Reputedly, it was constructed by the earliest Leinster king (Art Mess Telmann or Setna Sithbacc). Although these sites were deserted by the medieval period, they retained great symbolic significance (see Grabowski 1990).
Dún Ailinne is an oval hilltop site of about 15 hectares, enclosed by a bank and ditch with an entrance on the eastern side. It was excavated between 1968 and 1975. The main excavation area was on the top of the hill, near the center of the site. Here, pottery, flaked flint, and ground stone artifacts show Neolithic and (very slight) Bronze Age activity (see Johnston 1990). The nature of this activity is quite unclear, however, because of extensive disturbance by the construction of three successive circular timber structures in the Iron Age. These were large: The diameter of the first was 28 meters, the second 38 meters, and the last 42 meters. The entrance of each faced roughly east-north-east. Each in turn was dismantled and, after the last had been taken down, accumulations of burnt stone, ash, charcoal, and animal bone indicate periodic feasting. Radiocarbon dates for these Iron Age activities lie between the fifth century b.c.e. and the third century c.e., while bronze, iron, and glass artifacts are mostly of the first century b.c.e. and first century c.e.
Survey and excavation of the site entrance revealed a roadway eight meters wide running through the entrance into the interior. Its alignment is directly toward the entrances of the circular timber structures on the top of the hill. All available evidence indicates that Dún Ailinne in the Iron Age was a ritual and ceremonial site, which later fell into disuse (see Wailes 1990). The ENE orientation of the timber circles and the roadway suggests that they may have been aligned with sunrise on or about the festival of Beltane (1 May), the traditional beginning of summer. Pam Crabtree's 1990 analyses of the animal and plant remains suggest that Iron Age activities at the site were mainly around that time, and in the fall.
Crabtree, Pam. "Subsistence and Ritual: The Faunal Remains from Dún Ailinne, Co. Kildare, Ireland." Emania 7 (1990): 22–25.
Grabowski, Kathryn. "The Historical Overview of Dún Ailinne." Emania 7 (1990): 32–36.
Johnston, Susan A. "The Neolithic and Bronze Age activity at Dún Ailinne, Co. Kildare." Emania 7 (1990): 26–31.
Wailes, Bernard. "The Irish 'Royal Sites' in History and Archaeology." Cambridge Medieval Celtic Studies 3 (1982): 1–29.
Wailes, Bernard. "Dún Ailinne: A Summary Excavation Report." Emania 7 (1990): 10–21.