The name Smoo is thought to be derived from the Norse word "smjugg" meaning hole creek or cleft. This impressive sea cave has been carved into Durness limestone by successive episodes of high sea level over the past several hundred years. The huge entrance, the largest entrance of any sea cave in the British Isles is more than 15 meters high and leads into the first chamber which is more than 60 meters long and 40 meters wide. The second chamber, containing the waterfall, is about 21 meters by 9 meters and can be viewed from a specially constructed platform, the third chamber is accessible only by a small boat.
The Smoo burn Allt Smoo drops nearly 25 meters into the second chamber down a vertical shaft, the Falis Smoo or chimney Smoo as the as the sink hole in the roof is called. The burn cascades into a deep pool with a depth of around eight meters. After heavy rain, the Allt Smoo is changed into a raging torrent that crashes into the underground lochan with a gigantic roar. The "blow hole" and waterfall can be observed from an observation point above the cave.
The Allt Smoo, noisily pours in through a gap and falls 80 feet.
1858 A Journal of Richard Charles Weld, Two months in the Highlands, Orcadia and Skye reports that a 15 shilling charge was being made for a boat rip across a flooded chamber. Extra for lights
J, A : Smoo Cave, 22 pp 4 plates S typed MSS reprints accounts
of Scott, Heddle, Pocock, q.v, plates pub BC 9 11. article in BC 7 44-51
based on it; reprinted BC 53 36-39. Cave Sci .3 (22) 277-285, 287 a reprint.
1936 A detailed account of exploring the cave by R. Macdonald Robertson in a book Angling in Wildest Scotland
J, A : Smoo Cave, Millennial Star. pub the Latter-Day Saints.
103 (25) 394-396 illus 19th June.
J, A : Notes on Smoo Cave, Sutherland, Cave Sci 3 (22)
277-285,287. reprint of Pilling 1935 without plates.
1964 Standing, P: Smoo Cave, GSS Jl 3 (1) 18-19
D : Smoo Cave, Windy City Speleonews 5 1, 5, 6,
1968 Jeffreys, A, L. (): The Great Cave of Smoo, Jl Settle Group British Speleological Association pp l6-19 map S
1969 Pilling, J, A : Smoo Cave, BC 53 36-42 reprint of BC 7 44-51 based on Pilling 1935.
1972 Jeffreys, A, L: Ideas on the formation of Smoo Cave
Small entry in Discovery and Excavation in Scotland by Keillar .
1977 First attempts at a regular commercial excursion into the inner chambers
1981 A visit and an article written by Jim Johnston for the Scots Magazine
1985, the Highland Council spent forty five thousand pounds on land acquisition, car parking facilities, picnic site, footpath and viewing area improvements around Smoo.
1989, Smoo Cave was denotified as a Site of Special Scientific Interest.
1991 Cave was modernised, the footpaths improved and light installed.
2002 Report by John Finlay Associates addressing the development potential of Smoo Cave