The turnover among the staff of the underground complex was slow.

She led the way, eager to get out of the underground complex.

Scientists at a secret underground complex have found a way to travel to another dimension.

According to current plans the underground complex will be opened in 2015 and also include stations for two subway lines.

By the end of the 19th century, a large underground complex had also been built which served as quarters for the troops inside the city.

The underground complex never used again; it was destroyed in May.

After searching the entire underground complex the two fail to find anything.

There wasn't much room left in the underground complex below the Tower.

The underground complex was built 4 years, from 1957 to 1961.

But then, Joe reflected, so did the rest of the underground complex.