Palmyra was in the ancient times an important city of central Syria, located in an oasis 215 km northeast of Damascus and 120 km southwest of the Euphrates. It has long been a vital caravan city for travellers crossing the Syrian desert and was known as the Bride of the Desert. The Greek name for the city, Palmyra (Παλμυρα), is a translation of its original Aramaic name, Tadmor, which means 'palm tree'. Tadmor (in Arabic تدمر) is today the name of a small city next to the ruins, heavily dependent on tourism.Ancient
Temple of Bel.In the mid-first century A.D., Palmyra, a wealthy and elegant Syrian city located along the caravan routes linking the Parthian Iran with the Mediterranean ports of Roman Syria and Phoenicia, came under Roman control. During the following period of great prosperity, the Aramaean citizens of Palmyra adopted customs and modes of dress from both the Iranian Parthian world to the east and the Graeco-Roman west.
The city was first mentioned in the archives of Mari in the 2nd millennium BC. It was another trading city in the extensive trade network that linked Mesopotamia and northern Syria.
When the Seleucids took control of Syria in 323 BC, the city was left to itself and it became independent. The city flourished as a caravan halt in the 1st century BC. In 41 BC, the Romans under Mark Antony tried to occupy Palmyra but failed as the Palmyrans escaped to the other side of the Euphrates. The Palmyrans had received intelligence of the Roman approach. This proves that at that time Palmyra was still a nomadic settlement and its valuables could be removed at short notice. Palmyra was made part of the Roman province of Syria during the reign of Tiberius (14–37). It steadily grew in importance as a trade route linking Persia, India, China, and the Roman empire. In 129, Hadrian visited the city and was so enthralled by it that he proclaimed it a free city and renamed it Palmyra Hadriana.
Beginning in 212, Palmyra's trade diminished as the Sassanids occupied the mouth of the Tigris and the Euphrates. Septimius Odaenathus, a Prince of Palmyra, was appointed by Valerian as the governor of the province of Syria. After Valerian was captured by the Sassanids and died in captivity in Bishapur, Odaenathus campaigned as far as Ctesiphon (near modern-day Baghdad) for revenge, invading the city twice. When Odaenathus was assassinated by his nephew Maconius, his wife Septimia Zenobia took power, ruling Palmyra on the behalf of her son, Vabalathus. Zenobia rebelled against Roman authority with the help of Cassius Dionysius Longinus and took over Bosra and lands as far to the west as Egypt. Next, she attempted to take Antioch to the north. In 272, the Roman Emperor Aurelian finally retaliated and captured her and brought her back to Rome. He paraded her in golden chains but allowed her to retire to a villa in Tibur, where she took an active part in society for years. This rebellion greatly disturbed Rome, and so Palmyra was forced by the empire to become a military base for the Roman legions. Diocletian expanded it to harbor even more legions and walled it in to try and save it from the Sassanid threat. The Byzantine period only resulted in the building of a few churches and much of the city was in ruin.
FakhrEddin Castle on a Palmyran hill, (Arab castle):
The city was taken by the Muslim Arabs under Khalid ibn Walid. In the 6th century, Fakhreddine al Maany castle was built on top of a mountain overlooking the oasis. The castle was surrounded by a moat, with access only available through a drawbridge. The city of Palmyra was kept intact.
Look also my friend's blog Pictures of Syria.
Information from http://en.wikipedia.org/wiki/Palmyra