William Turpin

A view of the interior, taken from outside the one small window facing the door.

Navigatio Brendani 2.1:

conclūsit sē in ūnō ōrātōriō 

The oratory at Brendan's monastery in Clonfert was probably as simple as the famous Gallarus Oratory, on the Dingle Penninsula, though early churches were not all made from stone.  The date and purpose of the Gallarus Oratory have been disputed, but Tomaás Ó Carragáin, Churches in Early Medieval Ireland: Architecture (2010) considers it one of a number of drystone churches built sometime between 700 and 1100.

The oratory at Brendan's monastery in Clonfert was probably as simple as the famous Gallarus Oratory, on the Dingle Peninsula, though early churches were not all made from stone.  The date and purpose of the Gallarus Oratory have been disputed, but Tomaás Ó Carragáin, Churches in Early Medieval Ireland: Architecture (2010) considers it one of a number of drystone churches built sometime between 700 and 1100.

Navigatio Brendani 2.1:

conclūsit sē in ūnō ōrātōriō.

A chalice of the 8th or 9th century, found in 1980 with four other liturgical utensils (including a paten) near Killenaule, County Tipperary.  

Navigatio Brendani 12.43:

et eōrum vāscula similiter dē cristāllō, īdēst patēnae, et calicēs, et urceolī, et cētera vāsa quae pertinēbant ad cultum dīvīnum.

A pair of ptarmigans, in their white winter plumage (near Glencoe, Scotland).

Navigatio Brendani 11.8: 

avibus candidissimīs

In 1976 the adverturer Tim Severin crossed the Atlantic in this recreation of Brendan's currach, to show that the Irish could in fact have "discovered" America.

An 17th century Englishman, Captain Thomas Phillips, drew and described an Irish ocean-going boat (currach).  It had some planks, and a wooden keel and rudder, but the sides were made from treated hides.

This map from the late 18th century has an island west of the Canary Islands and notes that  "some authors place in this region the fabled Isle of St. Brendan (Isle de St. Borondon).