Bolin's Breach is one of the few passable routes across the Cloud-Ankled Mountains that define the southern extent of the Settled Lands. At its northern entrance, the Breach passes between Mount Nuth on the western side and Mount Orquond on the east, then winds a distance of 200 kilometres to the south, descending to the southern foothills of the Cloud-Ankled Mountains. During the months of deep winter the middle part of Bolin's Breach is above the snowline and impassable.

Travelling north to south, the journey through Bolin's Breach passes a number of landmarks:

Travellers to the south face a number of dangers on the way. Opportunistically anthropophagous hill tribes have settlements on the mountain slopes near the pass. Gargoyles and trolls are also known to sometimes watch the road and waylay those taking the passage over the mountains.

Near the southern entrance to the pass, some distance into Pteranodon Swamp, concealed among the mangroves, is the town of Sourwater.

At the northern entrance to Bolin's Breach, two roads lead out into the Settled Lands: a western road to Ys and another that takes a traveller north-east to Miklagard.

The Ys road leads north-west into the Forest of Baleful Eyes, wherein it reaches the town of Happenstance on the banks of the Pikefish River, thence the road continues on through the forest to Ys.