31 December 2015. In Najran, the thump of artillery reverberates all day across a valley ringed by desert mountains along Saudi Arabia’s southern frontier with Yemen. The city’s airport is closed, forcing residents to travel almost 300 kilometers (186 miles) to the nearest alternative.

BLOOMBERG

http://www.bloomberg.com/news/articles/2015-12-21/in-one-saudi-town

At industryabout.com:

Yemen - Industrial Facilities Map