Taken from New Climbs 1991.
Doonbristy 42m MXS
Start at the landward side of the ledge system at 15m on the west face. The route follows the seaward arete of the stack, mainly on the left-hand side. The stack became disconnected from the headland in 1393 and the fort on top has been isolated since then.
1/. 18m 5a/b Climb up right-wards over an interesting overhang (on good holds) to gain a shallow groove in a band of lighter coloured rock. Climb this to an excellent ledge on the arete.
2/. 24m 5a/b Climb onto a projecting ledge above the stance and gain a much smaller projecting ledge above. A short wall leads to a good ledge and easier (but loose) ground leading to the top.
M. Fowler, N. Duggan, S. Sustad May 1990.
Intended to repeat the above route but ended taking this line to the summit of Dún Briste sea stack
Chaos Theory 42m XS
There is a huge non tidal ledge system at base (approx 10m above the sea) of the west face.
1: 18m 4b From the seaward end of the walkable ledge make a couple of moves up to the grim looking overhang. After a couple of ups and downs hand traverse left above the void to the sanctuary of a large non tidal ledge. Climb up and over the steps above and crawl through the birded gap above.
2: 24m 5a/b At the far left of the huge ledge climb the well protected groove with a hard move onto the ledge system above. Run it out forever (8mish) to a small crack in suspect rock above. Climb grooves and ledge systems above to finish up a superb layback corner and awful chimney above.
Iain Miller, Paulina Kaniszewska 28/08/16