Since then, Petra has stood as the marquee remnant of Nabataean society. But excavations in Mada’in Saleh – part of the Al-Ula sector of Hejaz, Saudi Arabia – have continued, regardless. Archaeologist Rebecca Foote led the survey for the Royal Commission for Al-Ula, and in 2019 she explained to the BBC why excavators focused solely on finding artifacts using hi-tech means. Photo Credit: Nick Brundle Photography / Getty Images