The Quarru Beneath the Hills is a location on the MR Narrow Gauge Railway. It is very important to the engines, since it keeps them busy.
The quarry opened in 1880, around the same time as the Corris Railway, and used 7 locomotives including Stuart and Falco. 1,2, and 3(Falcon) are to Falcon's Design, 5(Rusty) and 6 were built to Rusty's design in 1940, while 4(Stuart) and 7 were built to the design of Stuart. Eventually, Stuart (4) and Falcon (3) did come, in 1947 when the Mid Maine closed. They went away again in 1951, this time to MR's Narrow Gauge Trust, which absorbed the quarry. All the engines now work here.
The quarry is mined for Coal, Iron, Lapis Lazuli, Redstone, Gold, Emerald, and Diamond.