They were trained military men and women, manning the nerve center of the system's entire defense structure.

The castle was built in 1278 as part of the Zittau region's defense structure.

The outpost became an important defense structure in the upper Michigan frontier.

But he knows how I feel about the defense structure.

Jihad has been part of the defense structure of this country for 20 years.

It has been a military defense structure for several times.

It doesn't mean you can tear up your entire defense structure.

Therefore, as France sees it, Europeans should build their own independent defense structures.

It is also possible to build defense structures, such as walls, gates, and towers.

A fortified defense structure has existed here since at least the fifth century.