From the first century BC the city of Palmyra, in the Syrian desert, grew rich from the caravan trade which linked the Persian Gulf and the Mediterranean. It was incorporated into the Roman Empire by the end of the first century AD. According to the Greek inscription, the couple shown on this funerary monument from Palmyra are called Viria Phoebe and Gaius Virius Alcimus. The majority of such inscriptions are in Aramaic, the spoken language of the region, so the use of Greek here is unusual, as is its placement in a rectangular panel below the figures. The fact that they have the same clan name suggests that they may be freed slaves of a brother and sister. He is holding a book-roll, possibly symbolizing education or rights over the grave, whereas the woman is holding a spindle and distaff, which may represent her household role. Tombs for the wealthier citizens were built outside the city in the form of towers of several stories, single-storey house tombs, or underground rock-cut tombs called hypogea. They contained compartments (cubicula) set in the walls to hold the bodies, which were often mummified. Each cubiculum was sealed with a plaque like this one, bearing a sculptured portrait of the deceased with a brief dedicatory inscription. Such monuments were known as a nefesh ('soul' or 'personality') and enabled the owner to exist in the next world. In the third century, under their queen, Zenobia, Palmyrene troops took control of Syria, conquered Egypt and attempted to take Asia Minor (modern Turkey). In AD 272 the Roman emperor Aurelian defeated the Palmyrenes, captured Zenobia and took her to Rome. Palmyra was destroyed after a second insurrection in AD 273.