At 135.1 hectares (333.8 acres) the airfield has three tarmac runways, a control tower dating back to the 1940s, a fire station and various underground structures from the decade.

BBC: Perranporth airfield up for sale

The EPA has subpoenaed Halliburton for the secret formula for the liquid chemical cocktail it pumps into underground rock structures so natural gas can be accessed through a process known as hydraulic fracturing or fracking.

FORBES: EPA subpoenas Halliburton over fracking

On the flip side, above-ground bunkers, rather than those built underground, are often handsomely proportioned, neoclassical structures.

WSJ: New Lives for Nazi-Era Bunkers