1.   It has a complex tunnel system built along the banks of slow moving waterways with many exits above and below water level.

2.   Around Cu Chi, all human life had taken cover in an increasingly elaborate tunnel system deep in the hard red earth.

3.   Forty feet of water collected in its garage, which contributed to flooding in seven institutions connected by a tunnel system.

4.   In the report one officer described chasing two white men into a tunnel system, and then dropping in a grenade, presumably killing them.

5.   The plants are wheeled to class through an elaborate underground tunnel system that protects against the cold.

6.   TNT, a New York-based builder of massive projection systems, installed a projection tunnel system that worked both for rodeo replay and concert video presentation.

7.   Tuesday, much of the tunnel system was unaffected, and was open.

8.   Col. Thanh said knowledge of the tunnel system was strictly limited.