Boating

Powerboat and WaveRunner rentals are available from Club Nautico, at the Boat Haven Marina, 1484 E. Tamiami Trail (tel. 239/417-3474), on the east bank of the Gordon River behind Kelly's Fish House; and from Port-O-Call Marina, also behind Kelly's Fish House (tel. 239/774-0479).

Cruises

Day Star Charters features the double-decked Double Sunshine (tel. 239/263-4949), which sallies forth onto the river and bay daily from Tin City, where it has a ticket office. The 1 1/2-hour cruises leave at 10am, noon, 2pm, and an hour before sunset. They cost $28 for adults and $14 for children under 12.

The Sweet Liberty (tel. 239/793-3525), a 53-foot sailing catamaran, makes 3-hour morning shelling cruises to Keewaydin Island. The vessel then spends the afternoon on 2-hour sightseeing cruises (you'll usually see dolphins playing in the river on this one) and 2-hour sunset cruises on Naples Bay before docking at Naples City Dock, 880 12th Avenue South. Shelling cruises cost $38 for adults, $15 for children 12 and under; sightseeing and sunset cruises cost $27 for adults, $15 for children 12 and under.

For a good deal more luxury, the 83-foot Naples Princess (tel. 800/728-2970 or 239/649-2275) has narrated breakfast, lunch, and sunset dinner cruises from Port-O-Call Marina, on the eastern shore of the Gordon River. With their extensive buffets, the sightseeing, sunset, and shelling cruises are good values, ranging from $25 to $50 per person. The cost for children 12 and under is $15 on all cruises. Call for schedules and reservations.

Fishing

The locals like to fish from the Naples Pier. The pier has tables on which to clean your catch, but watch out for the ever-present pelicans, which are master thieves. You can buy tackle and bait from the local marinas. The pier is open around the clock, and admission is free. No fishing license is required.

The least expensive way for singles, couples, and small families to fish without paying for an entire boat is on the 45-foot Lady Brett (tel. 239/263-4949), which makes two daily half-day trips from Tin City for $60 for adults, $50 for kids under 12. Rod, reel, bait, and fishing license are included, but bring your own drinks and lunch. Its sister boat, the Captain Paul, goes on half-day backcountry fishing trips, departing daily at 9am. These cost $60 for adults, $50 for kids 12 and under.

A number of charter boats are based at the marinas; call or visit them for booking information and prices.

Scuba Diving

Kevin Sweeney's SCUBAdventures, 971 Creech Rd., at Tamiami Trail (tel. 239/434-7477), which also has a base on Marco Island, takes divers into the Gulf, teaches diver-certification courses, and rents watersports equipment.

Tennis

In Olde Naples, the city's Cambier Park Tennis Center, 755 8th Ave. S., at 9th Street South (tel. 239/213-3060), is one of the country's finest municipal facilities. In fact, it matches those found at many luxury resorts. To play on its 12 lighted clay courts, it costs $25 an hour. Book at the pro shop in the modern building, which has restrooms but no showers. The shop is open Monday through Friday from 8am to 9pm, Saturday and Sunday from 8am to 5pm.

Watersports

Naples Watersports, 550 Port A Call Way (tel. 239/774-0479), will hook you up with WaveRunners, jet skis, and the requisite water toys. Hobie Cats and windsurfers can also be rented on the beach at the Naples Beach Hotel & Golf Club, 851 Gulf Shore Blvd. N. (tel. 239/261-2222); and at Clam Pass County Park, at the end of Seagate Drive (tel. 239/353-0404).