De Aar means "the artery" and in many senses this town is also the lifeblood of the Karoo. It is the head office of the Emthanjeni Municipality and the Pixley ka Seme District Municipality; home to many artists; there is an important weather station that can be toured by visitors, and it is still an important railway junction.

The significance of its situation on the railway line is because it is central to Gauteng, Cape Town, Port Elizabeth and Namibia. There are about 110km of railway lines including 29 rail tracks in the De Aar precincts.