The Lajat (/ ALA-LC: al-Lajāʾ), also spelled Lejat, Lajah, el-Leja or Laja, is the largest lava field in southern Syria, spanning some 900 square kilometers. Located about southeast of Damascus, the Lajat borders the Hauran plain to the west and the foothills of Jabal al-Druze to the south. The average elevation is between 600 and 700 meters above sea level, with the highest volcanic cone being 1,159 meters above sea level. Receiving little annual rainfall, the Lajat is largely barren, though there are scattered patches of arable land in some of its depressions.
The region has been known by a number of names throughout its history, including "Argob" ( Argov,) in the Hebrew Bible and "Trachonitis" by the Greeks. Long inhabited by Arab groups, it saw development under the Romans, who built a road through the center of the region connecting it with the empire's province of Syria. The pagan cults that predominated in Trachonitis during the Roman and pre-Roman era persisted through much of the Byzantine era, until the 6th century when Christianity became dominant. During Byzantine rule, Trachonitis experienced a massive building boom with churches, homes, bathhouses and colonnades being constructed in numerous villages, whose inhabitants remained largely Arab.
At some point the region was abandoned, but repopulated by refugees from other parts of Syria during the 13th-century Mongol invasions. It was then that the region gained its modern Arabic name, al-Lajāʾ, which means "the refuge". During early Ottoman rule in the 16th century, the Lajat contained numerous grain-growing villages, but by the 17th century, the region was all but abandoned. Local Bedouin tribes, such as the Sulut, increasingly used the region for grazing their flocks, and Druze migrants from Mount Lebanon began settling the area in the early 19th century. Today, the population is mixed, with Druze inhabiting its central and eastern areas, and Muslims and Melkites living in villages along its western edge.