Israel's four seas (the Mediterranean, the Sea of Galilee, The Dead Sea, and the Red Sea) offer an amazing variety of swimming experiences. The beaches of Israel look beautiful, but be careful about going in the water. Unusually strong riptides, whirlpools, and undertows along the Mediterranean coast can claim the strongest swimmer. Never swim in unguarded areas. Along much of the coast, especially north of Tel Aviv, the beaches seem sandy, but a few steps into the surf, and you're standing on a rocky shelf -- not a good place to be when waves come crashing down. Pollution is also a serious problem, as it is throughout the Mediterranean. Israel's beach standards are much higher than those of most Mediterranean countries, but on many days, garbage from other countries swirls along the coast. At Nahariya, Akko, and the Poleg Nature Reserve (8km/5 miles south of Netanya), which have no sewage-treatment plants, I would hesitate to put a toe, no less my head, in the water. Expect beaches to be lively; Israelis play compulsive paddleball on any stretch of beach they're on, regardless of sleeping sunbathers in the line of fire. And watch out for sea urchins and stinging coral in the Red Sea and the burning medusas (jellyfish) that attack the Mediterranean beaches in July.