Massive disused lime kilns on the Monsal Trail at Millers Dale. Lime has been used as a building material and to improve the soil for centuries. Even the Romans used lime in their concrete. Up to the 18c however lime production was very much a small scale family affair with families living next to their kiln in limestone hillsides and the whole family involved in the production. With the coming of the railway and an increased demand from the steel and chemical industries in the 19th century lime production made a step change. These lime kilns are the biggest I’ve seen and were built next to the quarry where the limestone was obtained and to the old Midland Railway to take the finished lime away. They were in operation from 1880 to 1944 producing at their peak 50 tons of quicklime per day. The kilns now provide habitats for swifts and three species of bats.