The two-day casting call, for the hit series' sixth season, was posted by the ModExpoR agency, which set down precise selection criteria.
Would-be extras must be between "18 and 65 years old, Mediterranean, with very dark or black skin".
Men must be at least 1.75 meters (five feet seven inches) tall, women at least 1.7 metres (five feet six inches), and slim-built.
David, 20, who got up at 6 a.m. to drive two hours to the casting call, said he was worried about his chances.
"I was quite nervous to see people better than me standing in the queue. People with longer hair, darker skin, and who were taller than me and had a better profile," he told AFP by phone.
"I told myself they might not take me."
Boasting picturesque beaches and Moorish architecture, the city was the location for films "Clavius" in 2014 and "Exodus" in 2013.
The area has appeared in nearly 500 films over the past 60 years, according to the local tourism office.