Curanov had crossed deserts, explored the Arctic Circle on foot, gone spelunking in countless different subterranean systems.

So, many Sniks slowly immigrated to Mars, and developed a subterranean system of paths and supply lines.

He realized that the Gom atmosphere was nearly identical with that on Earth but he didn't know the composition of the air inside the subterranean system.

I supply the organic substance and they build the subterranean system for me which enables me to produce a greater amount of the organic substance.

They discovered that the small caves were actually subterranean developed system of caverns with lakes and rivers.

In the case of Hodotermes mossambicus, the diffuse subterranean system of spherical hives may be located from near the surface to more than 6 m deep.

If they had ever gone down into the subterranean system, it had been so long ago that the honkers had no record of it.

Many parts of Slovenia have a carbonate ground, and an extensive subterranean system has developed.

I had discovered that the subterranean systems of the department of power and water interfaced with the flood-control-project tunnels at least at a few points.

It's your subterranean system.