which were the prominent cities?
Berut, Arqa and Baalbek.
Phoenicia
Numerous other cities existed in the Levant alone, many probably unknown, including Berut (modern Beirut) Ampi, Amia, Arqa, Baalbek, Botrys, Sarepta and Tripoli. 
who opened trade between india and the mediterranean world The Roman Empire. which items were traded? Animals. which were the major ports on the roman side? Arsinoe, Berenice and Myos Hormos. when was this trade started? 130 BCE through which waterbody did this trade take place? Mediterranean Sea. which ancient civilizations were there around it apart from the one discussed above?? The Greek city states and the Phoenicians. when did the last civilization reach its peak? In the Iron Age. did they colonize any area? They established numerous colonies and trading posts along the coasts of the Mediterranean. which were the flourishing industries there? Glass-making, engraved and chased metalwork.
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Phoenicia [SEP] Important cities and colonies
The Phoenicians were not a nation in the political sense, but were organized into independent city states that shared a common language and culture. The leading city states were Tyre, Sidon, and Byblos. Rivalries were common, but armed conflict rare. Numerous other cities existed in the Levant alone, many probably unknown, including Berut (modern Beirut) Ampi, Amia, Arqa, Baalbek, Botrys, Sarepta and Tripoli. From the late tenth century BC, the Phoenicians established commercial outposts throughout the Mediterranean, with Tyre founding colonies in Cyprus, Sardinia, Iberia, the Balearic Islands, Sicily, Malta, and North Africa. Later colonies were established beyond the Straits of Gibraltar, particularly on the Atlantic coast of Iberia, and the Phoenicians may have explored the Canary Islands and the British Isles.