Through their control of the region's wells, the Garen rulers effectively held a monopoly over their nomadic subjects as they were the only hydraulic empire in Africa during their reign. Large wells made out of limestone were constructed throughout the state, which attracted Somali nomads with their livestock. The centralized regulations of the wells made it easier for the nomads to settle disputes by taking their queries to government officials who would act as mediators. Long distance caravan trade, a long-time practice in the Horn of Africa, continued unchanged in Ajuran times. Today, numerous ruined and abandoned towns throughout the interior of Somalia and the Horn of Africa are evidence of a once-booming inland trade network dating from the medieval period.