Hobbs Quarry Nature Reserve is one of the smallest and least visited of over 60 sites managed by Gloucestershire Wildlife Trust, enclosing part of an old limestone quarry, established in the 1600s and abandoned since the end of the 19th century, and bordering a patch of ancient woodland, Coleman's Wood. This section of the quarry is also a Site of Special Scientific Interest (SSSI), on account of the interesting geology and the range of marine fossils found in the exposed rocks, while for nature the place is notable for dormice and several bird species. The quarry has over the last century been colonised by many of the plants found in the adjacent woodland, of which most are common, the two rarer species being herb paris and greater butterfly orchid.
The quarry is long and narrow, following a line of exposed, folded and uplifted Silurian-period limestone orientated north to south; excavations have left a low, vertical, east-facing cliff with an overgrown gully in front. Most of the rock is from the Nodular Beds Member of the Wenlock Limestone formation, overlain by other limestone, more obviously stratified. The adjoining parts of the quarry, outside both the nature reserve and the SSSI, extend in both directions to form a continuous trough nearly one mile long.
The nature reserve is reached by a narrow lane that leaves the A40 to the southwest, at Dursley Cross, 7 miles west of Gloucester. After a third of a mile a narrow track forks off southwards, leading to the quarry, with parking space for a couple of vehicles at the junction. The lane continues a short distance to a house, after which it becomes private. Opposite the junction is a footpath that follows the edge of the northern part of the quarry, alongside Kiln Wood and into Sculchurch Wood, while the protected area, in the nature reserve, begins just a few feet down the track, and is identified by a Gloucestershire Wildlife Trust notice. The track runs along the east rim of the quarry for 700 feet, past the remains of an old limekiln, then exits the reserve into Coleman's Wood. Within the reserve, the northern part of the quarry is relatively unvegetated, kept clear of scrub to display the strata in the cliff face, while the south end is much more overgrown. Wildflowers are concentrated in the sunny areas, below the northern cliff face and around the kiln. All can be seen in less than half an hour.