Ar (Heb. id. עָר i.q. עַיר, a city; Sept. ῎Αρ [v. 1:῎Ηρ in Nu 21:15], De 2:29; fully Ar-Moab, Nu 21:28; Isa 15:1; also city of Moab, Nu 22:36; prob. also for Mooabitis or the whole country, De 2:9,18), the capital city of the Moabites (Nu 21:28; De 2:9,18,29), near (south of) the river Arnon (De 2:18,24; Nu 21:13-15). It appears to have been burnt by King Sihon (Nu 21:28), and Isaiah, in describing the future calamities of the Moabites, says, "In the night Ar of Moab is laid waste and brought to silence" (Isa 15:1). In his comment on this passage, Jerome states that in his youth there was a great earthquake, by which Ar was destroyed in the night-time. This he evidently regards as a fulfillment of the prediction, which, however, had probably some less remote reference. Latterly the name of the city was Graecized Areopolis (Α᾿πεόπολις, q. d. "city of Mars"). It was an episcopal city of the Third Palestine (Reland, Palaest. p. 577 sq.). According to Theodoret (Comment. in Isa 15; Isa 29), it was sometimes called Ariel. This city was also called Rabbah or Rabbath, and, to distinguish it from Rabbath of Ammon, Rabbath-Moab. Ptolemy calls it Rabmathon; Steph. Byzantinus, Rabathmoma; and Abulfeda, (Tab. Syr. p. 90), Rabbath, and also Mab. Hengstenberg (Bileam, p. 236) thinks it is the modern Mehalet el-Haj, near the Arnon (Burckhardt, 3, 636); but it is usually identified with the site that still bears the name of Rabba, visited and described by Seetzen, Burckhardt, Legh, Macmichael, and Irby and Mangles. It is about 17 miles east of the Dead Sea, 10 miles south of the Arnon (Mojeb), and about the same distance north of Kerak (Robinson, Researches, 2:569). The ruins of Rabbah are situated on a low hill, which commands the whole plain. They present nothing of interest except two old Roman temples and some tanks. Irby and Mangles (Letters, p. 457) remark, with surprise, that the whole circuit of the town does not seem to have exceeded a mile. Burckhardt says, "half an hour in circuit," and that no trace of walls could Le found; but it is obvious from the descriptions that the city whose ruins they saw was a comparatively modern town, less important and extensive than the ancient metropolis of Moab (Syria, p. 374, 377). SEE MOAB.