Peter Gomes, a Harvard theologian, writes:

“There is in Celtic mythology the notion of ‘thin places’ in the universe where the visible and the invisible world come into their closest proximity. To seek such places is the vocation of the wise and the good — and for those that find them, the clearest communication between the temporal and eternal. Mountains and rivers are particularly favored as thin places marking invariably as they do, the horizontal and perpendicular frontiers. But perhaps the ultimate of these thin places in the human condition are the experiences people are likely to have as they encounter suffering, joy, and mystery.”

Mountains and Rivers and

Mysteries as the clearest communicators between the temporal and the eternal – yes, for me, absorbed in those sacred places in nature and contemplating the Great Mystery, the visible and invisible are almost merged.  The veil is thin and the feeling is of a wondrous oneness.