Many of these tower houses are located on the border of the Burren barony, leading historians to believe that they were built by the ruling O’Loughlin clan to defend the coveted winterage lands of the Burren. Leamaneh & Dunguaire Castle are two good examples of this.

Winterage/Transhumance: The Burren is the only region in Europe where cattle are moved to lowlands in summer and to highlands in winter, in what is referred to as reverse transhumance. The so-called Burren winterages are the summits of the local hills which peak out at around 250 metres (830 ft) above sea level. Amazing as it may seem, these markedly flat uplands provide rich natural grazing for livestock, especially cattle and goats, all year round. Particularly, during the winter months, the temperate Atlantic climate, coupled with the free-draining rock and brightly coloured limestone rock, combine to encourage almost continuous grass-growth in the sheltered grykes and hollows in the limestone. The heat retention capacity of this massive block of limestone, over 700m thick in places means that local farmers actually over-winter large numbers of livestock on these hills from October to April. This unique practice dates back for hundreds if not thousands of years - witness the words of Ludlow in 1651 - and may well explain the very perceived paradox of the Burren as "fertile rock". The happy existence of over 1,000 feral goats is testament to the efficacy of such farming techniques.