These are what’s left of the historic Redstone “Beehive” Coke Ovens.
In the late 1890’s, Colorado Fuel & Iron company started mining operations to extract coal from the earth and convert it to coke (a form of fuel, not the soft drink). That company ceased operations in 1908 and the ovens sat idle until 1956 when Mid-Continent Coal & Coke Company resumed mining operations (although they may or may not have used the ovens – probably not. Update – they used more modern coking technology). Three events – an explosion in 1959 which killed 9 workers, another explosion in 1981 which killed 15 more workers, and a disastrous fire in 1990 caused that company to cease operations in 1991.
The little town of Redstone did survive, even though there is not local industry to support it.