Spoil mounds indicate the presence of an early eastern shaft at SJ 2070 6770, now located on wasteground south of modern housing. To the east of the sett, a single remaining shaft stands at SJ 2140 6740, marking the northern edge of the Rhosesmor Quarry.

The ruins of the mining infrastructure are particularly evident in the quarry area north of the A541. The Grade II-listed engine house at SJ19806780, which housed a 100-inch pumping engine, still stands alongside its adjacent brick chimney. The red-brick engine house built in 1917 for electric motors powering Taylor’s Shaft pumps remains in place at SJ 2040 6780.

Evidence of transport infrastructure is still present underground, where the former diesel railway system that connected the Halkyn District United Mines persists within the drainage tunnel. This railway once transported both miners and ore between the Pen-y-bryn Shaft and Olwyn Goch Shaft on the Hendre Vein.

Above ground, several mine buildings have survived. The offices, changing rooms, bath houses, and lamp rooms associated with Olwyn Goch Shaft remain intact.

The Hendre Mines worked the east-to-west Coed-Hendre Vein, located southwest of Nant-figallt Woods. Operations in the area date back at least to the mid-19th century, with the Hendre Ucha Mining Company active in Rhydymwyn between 1861 and 1866. Mining expanded along the vein, with principal shafts including Fron, Victoria, Mostyn Old Shaft, Engine Shaft, Olwyn Goch, and Taylor’s Shaft.

By the late 19th century, mining activity had become concentrated in an area north of the A541 and the disused Mold-to-Denbigh Railway. This section of the sett featured three large engine houses, boiler houses, and chimneys. The remains of an engine house and chimney can still be found at SJ 1982 6780, while another engine house stands at SJ 1980 6780. The third, along with its associated shaft and chimney, was located at SJ 1970 6778, now within the bounds of the Rhosesmor Quarry.

In 1928, the Halkyn District United Mines incorporated the Hendre Mines into their larger mining operation. The company reopened and deepened the Olwyn Goch Shaft to 490 feet, using it as the main access point for personnel. It also played a crucial role in the ventilation system, functioning as a down-cast shaft and handling waste removal. Nearby, the Taylor’s Shaft was repurposed for pumping operations during World War I under the direction of the Ministry.

Mining operations ceased in 1977, but maintenance and tunnel repairs continued until 1987, marking the final phase of activity at the site.