With a short time frame, these islands are an excellent choice. Highlights of a Saronics cruise generally include bustling Poros, the closest of all the Greek islands to the mainland, separated from it only by a picturesque, narrow channel offering views of the island on one side and the craggy, green mountains of the Peloponnesus on the other; and Hydra, steeped in history and one of the most beautiful harbors in Greece, lined by the homes built by sea captains in the 18th century. Often called the "St. Tropez of Greece," Hydra attracts its share of the rich and famous along with hordes of tourists arriving by day boat, but the cobbled streets, donkeys (donkeys are used for all kinds of transport, as there are no cars on the island), and whitewashed bougainvillea-draped walkways up away from the harbor make it the favorite of most who choose a Saronics cruise. Spetsai, not far away, has its own upscale charm, and though there are cars on the island, horses and buggies still clack along the waterfront streets. Aigina, Greece's first capital and the island where the first Greek coin was minted in 650 B.C, is the site of the Doric Temple of Aphaia. This shrine, built for the goddess of wisdom and light, is one of the most well-preserved ruins on any Greek island.