Lat: 50°51'4.92"N Lon: 5°41'27.50"W
The Caestert quarry system, located near Maastricht, Netherlands, is one of the most astonishing and extensive undergrounds on the planet. This ancient, subterranean maze of towering stone passageways can be measured in miles—well, kilometers—and it’s all been carved out of solid marlstone, a variety of limestone used in the construction of nearby cathedrals, abbess, and castles. A number of these massive, monumental buildings still stand throughout the region, owing thousand-year debts to the masons and quarrymen who once labored in dank conditions beneath ground, sawing stone by flickering candlelight.
It is a real thrill to duck inside of this place. Jacquo Silvertant, a local resident whose passion and cause is the preservation of Caestert, guided me past the graffiti sprawled concrete wall that blocks one of the quarry’s main entrances, making access into this historic site feel more like doing Soviet-era urbex than stepping back into medieval times. But after we slipped past the chopped-out rebar and ignited our gas lamps, my eyes adjusted to magnificent and mysterious spaces around me that felt much more spiritual than industrial.
We strode into a cavernous immensity that overwhelms. Just beyond the entrance, 50’ ceilings loom overhead. The yellowy-white marlstone walls and pillars have all been carved by quarrying methods dating back five hundred years or more, each surface bearing the repeated patterns of sawn-stone blocks removed one over the next. What had been left behind are the remains of determined human industry, enormous spaces hewn by hand from solid earth.
Caestert is an excellent example of medieval quarrying techniques and for this reason alone worthy of preservation efforts. But it is another element that truly distinguishes this subterranean labyrinth from many others found across Europe. It is the prevalence of ancient scrawled insignia, symbols, and drawings on the limestone walls, indicating that this quarry was the site of significant gatherings of men being instructed in both technical and spiritual matters. Such gatherings would have been highly suspicious, even blasphemous, in the eyes of the local religious community. The Clergy viewed any organization of quarrymen and masons as a seditious threat to their authority--an underground movement in more ways than one. The Caestert stoneworkers were part of a growing European trade-guild movement that, over time, would lead to widespread social and political revolution. What happened in the Caestert quarries, as evidenced by the scribbled illustrations and symbols, were the earliest tremors of future tectonic shifts that would one day rock the entire continent. Get it? Rock.