Jordan–Syria border

Mandate lines

After the First World War Amir Faysal pressed for Arab independence and in March 1920 accepted the crown of Syria, but the San Remo conference that April gave France a mandate for Syria and Lebanon and Britain one for Palestine with Transjordan. French forces defeated Faysal’s army at Maysalun in July 1920 and occupied Damascus. Transjordan became a semi-autonomous principality in 1922 and independent in 1946.^[1]

A Franco-British convention of 23 December 1920 described the line only in general terms; today’s boundary rests on a protocol signed in Paris on 31 October 1931. It follows the Yarmuk and its tributaries for about 24 miles, with Syria keeping the old railway along the river, then runs southeast about 80 miles in straight lines and northeast about 129 miles to the Iraqi tripoint. North of the Yarmuk rises the Jabal ad-Duruz, a volcanic massif whose lava country reaches into Jordan; the Yarmuk valley itself grows wheat, barley, vines and olives.^[1]

“The “crossroads” character of its geographic posture is thus reflected.”^[1]

Crossing and smuggling

Before Syria’s war the Nasib–Jaber crossing carried hundreds of trucks a day between Europe, Turkey and the Gulf. It partly reopened in 2018 after government forces drove rebels from the south, and Jordan fully reopened it on 29 September 2021, though trade had not recovered to its prewar level of about $1 billion.^[2]

Captagon, an amphetamine-type stimulant, became the al-Assad government’s largest export during the war; Damascus denied any involvement, while analysts estimated the trade brought in billions of dollars. In December 2025, a year after al-Assad’s fall, Jordan’s military struck smuggling sites in Syria’s Suwayda governorate, which it said were launch points for trafficking into Jordan.^[3]