Lost in 1975, while salvaging coal from another ship lost nearby, her funnel is visible at low water making her easy to locate. A good shallow dive or wreck dive for novices, lying in a reasonably sheltered position.

The Ballista was a 200t iron steamship used as a salvage vessel. 
She became a shipwreck while salvaging coal from a vessel called the River Tay, which she then sunk directly on top of after a severe gale swept the west coast of Scotland on the 5th and 6th of February 1973, breaking her stern mooring.

The wreck’s mast was visible for many years on the westerly point of Eilean Rubha an Ridire, but has now sunk, although parts of the superstructure still appear above the surface at low springs.

Lying between 3-10 metres,the hull is fairly intact and upright. The site is sheltered from the strong currents of the Sound, and the keel of the River Tay is still visible beneath her. She actually lies on top of 2 other wrecks, one of which may be the drifter Ardfern, the other being the River Tay. Care should be taken as slightly away from the sight there can be quite strong currents.

BSAC Wreck Register May 87, No 40
Moir and Crawford 1997, 157-8