What bodies of water surround Rome and what rivers flew through it and how did this benefit the ancient Romans?

The city of Rome was not (and still is not) surrounded by the sea. The city of Rome was (and still is) in a peninsula: Italy. Italy is in the Mediterranean Sea. It was the Roman Empire which surrounded the Mediterranean sea. Rome conquered all the lands on the shores of this sea.

The city of Rome is on the only ford on river Tiber. This made Rome in her early days the main north south communication centre in the region. The river also provide a navigable access to the sea which was 14 miles away (16 miles nowadays). The Roman built a port in the city, on the river, and a bigger port at Ostia, on the coast.

The Roman Empire benefited from being centred on the Mediterranean because this sea acted as a means of communication between the lands on its shores and facilitated the growth of a thriving trading network around the empire. Shipping was intense and goods were shipped all around this sea.