The hill is managed by Shropshire Wildlife Trust and includes 540 million year old ripple beds and ancient pre-Cambrian lava flows in exposed quarries.

The exposed quarries are popular with other butterfly species, including the green hairstreak and wall, which like to bask in sheltered spots.

The rhyolitic rocks themselves are representative of explosive volcanic centres to the west of this site and beyond the Church Stretton lineament.

[4] The thermal expansion of the area is likely to have assisted the formation of a sedimentary basin in which such volcaniclastic sediments accrued and were later folded.

[3] In 2017, the discount retailer Poundland launched a rival chocolate bar to the Toblerone, which is manufactured by Mondelēz.

Poundland's bar, Twin Peaks, takes the design of its shape from The Ercall and Wrekin hills.

Poundland is based in the West Midlands, and its founder, Steve Smith, lives near Bridgnorth in Shropshire.