Before going back to the shadowy past, let us endeavour to trace amongst its ruins the outlines of the ancient buildings, and to explain the special use and meaning of each in the monastic economy, when white-robed monks trod its cloisters, and knelt and prayed before the altars in its church. Each of the Cistercian churches and monasteries was built upon a uniform plan, with some slight modifications, arising perhaps in all instances from peculiarities of site and local difficulties. Around the whole pile of monastic buildings, and girdling an area of some thirty acres or more, comprising gardens, orchards, meadows, ran a high wall, called the "Enclosure Wall," which served to isolate the denizens of the cloister, and prevent as far as possible all ingress of the world. Entrance within the precincts of the monastery was obtained through a spacious and lofty gate-house occupied by a trusty Lay-Brother, whose duty it was to receive visitors, and dispense hospitality to the poor and the way-farer; thus he formed a connecting link between his brethren within and the world without, from which they were cut off. Extending on either side of this gate-house, or "Porter's Lodge," as it was known in monastic language, was a range of buildings for the exclusive use of strangers of every grade. There were the Hospice proper, an infirmary for the sick poor, with stabling also, in the immediate vicinity, for the horses of travellers:-- "Whoever passed, be it baron or squire, Was free to call at the abbey and stay; No guerdon or gift for his lodging pay, Though he tarried a week with its holy choir." The old tower which is passed as one approaches the ruins of Mellifont, was the "Porter's Lodge," and right under it ran the avenue which led to the abbey, but which was converted into a mill-race when Mellifont had reached its last stage of degradation. The present road-way was constructed in order to give access to the mill. The remains of old walls can still be traced stretching on both sides of the tower, and prove its ancient purpose in connection with Cistercian usage, as described above. Some gate-houses of Continental monasteries, which have till now subsisted intact from the eleventh or twelfth century, bear a striking resemblance to this one at Mellifont. That of Aiguebelle, in particular, near Grignan, in the Department of Drôme, France, most closely resembles it.