Getting away, at least temporarily, wouldn't be a problem unless the FBI knew that the buildings on each side of his were connected underground.

"They must all be connected underground," Marguerite said.

The colliery was connected underground with two other local Charlesworth pits, Warren Vale Colliery and Kilnhurst Colliery.

The collieries at Roundwood and Silverwood were connected underground in 1908.

Much of the castle was connected underground, and the Kitchen Keep was no exception.

The 170 km long pipeline was constructed in the qanat technology, that is as a series of well-like vertical shafts, which were connected underground from opposite sides by gently sloping tunnels.

The colliery was connected underground with two other mining operations, Warren Vale Colliery and Warren House Colliery.

The Hermann and the Fiedler were connected underground, he wrote, and the Fiedler was flooded and overflowing into Clear Lake.

However, in 1968, the two collieries were connected underground by the Bewick Drift, from which coal was brought to the surface.

The first coal was raised in 1902, with the workings connected underground to the Universal Colliery in Senghenydd for ventilation purposes.