During the high season only, you'll find a helpful Rhodes Municipal Tourist Office at Plateia Rimini, facing the port taxi stand (tel. 22410/35-945). It dispenses information on local excursions, buses, ferries, and accommodations, and offers currency exchange as well. Its hours are Monday through Saturday from about 9am to 9pm, Sunday from 9am to 2pm. The above-recommended Triton Holidays is also willing to answer any traveler's question, free of obligation, and is sometimes open when the tourist offices are closed.
City Layout -- Rhodes is not the worst offender in Greece, but it does share the country's widespread aversion to street signs and numbers. This means that you need a map marked with every lane, so that you can count your way from one place to another. My favorite is the map of Rhodes Town (Old and New) drawn by Mario Camerini; no longer widely available, I found it recently at a gift shop at 65 Socratous.
Rhodes city (pop. 50,000) is divided into two sections: the Old Town, dating from medieval days, and the New Town. Overlooking the harbor, the Old Town is surrounded by massive walls -- 4km (2 1/2 miles) around and, in certain places, nearly 12m (40 ft.) thick -- built by the Knights of St. John. The New Town embraces the old one and extends south to meet the Rhodian Riviera, a strip of luxury resort hotels. At its northern tip is the city beach, in the area called 100 Palms, and famed Mandraki Harbor, now used as a mooring for private yachts and tour boats.