Rob, looking to enlist Jenny in the unfolding situation, races from point to point along the bicoastal subterranean network.

Murdoch was beginning to wonder just how much there was of this incredible subterranean network.

The column of hot air rising in the aboveground mounds helps drive air circulation currents inside the subterranean network.

"I'm free," he observes as he and his sister leave the old woman in search of what they imagine to be a vast subterranean network.

The 160-year-old water system is a subterranean network of tunnels with thousands of miles of pipelines.

Restorations completed in 1985 have reopened the extensive subterranean network to visitors.

The fortification has a subterranean network of 3 east-west tunnels under the structure connected by a north-south tunnel.

For the time, the system was thoroughly modern, even high-tech, a subterranean network for priority and first-class mail fueled by pressurized air.

American's subterranean network, which also handles 480 bags a minute, was opened last October.

The entire subterranean network is commonly but mistakenly referred to as "the catacombs".