Precipitous Bluff or PB is a mountain in the South West Wilderness of Tasmania located north east of New River lagoon.

It is visible from the South Coast Track and the Moonlight Ridge walk with a prominence of over 400m consisting of columnar Jurassic dolerite rock.

[2][3][4] It is rich in Ordovician Carbonates and limestone in the area was briefly under threat by mining in the 1970s.

There were also logging threats until it became part of the Southwest National Park.

It is a 2-day walk from the coast track including a lengthy wade through New River Lagoon, or a multi-day hike across the more inland ridges.