Dehri lies on the bank of the Sone River with an average elevation of 99 metres (324 feet). It has a Railway station on the Gaya-Mughalsarai section of Grand Chord railways route. Until 1984, it had three railway stations. There were two separate railway stations called Dehri–on–Sone - one for narrow gauge Dehri Rohtas Light Railway and one for the Grand Chord Line. The two railway stations had no rail link because of gauge difference and were separated by a road called Station road. The third station, Dehri City Railway station, was situated at the centre of the town on Dehri-Rohtas light Railway route. The Grand Trunk Road/(NH 2) passes through the heart of the town. Dalmianagar, an industrial town is close to Dehri. Dehri is also called Dehri-On-Sone and sometimes combined as Dehri-Dalmianagar. The main occupation of the local population is agriculture - principally rice. Limestone, sand and coal is also mined
