You don’t have to be a guest at the Gamboa Rainforest Resort hotel  to use its activities center (8 A.M.–6 P.M. daily) or book its tours, which include bird-watching walks and night “safaris” on the lake. It rents kayaks, bicycles, and other toys. You can also charter fishing boats here, but expect to pay for it.
The aerial tram (9:15–10:30 A.M. and 1:30–3 P.M. Tues.–Sun., US$53 pp) is one of the star attractions of the resort. It’s sort of like a ski lift that takes passengers up about 80 meters to a hill, passing through the canopy of a patch of secondary forest along the way. A bilingual naturalist guide travels along in each four- or five-person gondola to spot and describe flora and fauna.
Passengers can get off at the top and climb a 30-meter observation tower that offers panoramic views of the Panama Canal , the Chagres , and the surrounding forest. The trip takes a little over an hour, not including the stop at the observation platform.
Don’t get your hopes up about seeing too much wildlife; these canopy trams are a comfortable way to experience tropical forest, but a quick zip through the trees is unlikely to net many encounters with animals. Particularly since the tram doesn’t start running until mid-morning, by then most birds and jungle critters have slipped away. In two visits, my biggest scores have been a glimpse of the tail of a sleepy kinkajou in the crook of a tree, and a roadside encounter with a group of coatimundis on the ride back to the hotel. In my opinion, the rate is excessive for what you get, but if you’re lucky enough to glimpse something special, you might feel it’s worth it.
Contact Gamboa Rainforest Resort  for reservations and information.
Before or after a tram ride it’s worth wandering around the resort’s flora and fauna exhibits. They’re housed in a series of structures on the road leading up to the tram and include an orchid nursery, a serpentarium with impressive native and nonnative species, a butterfly house, and a small freshwater aquarium that also contains crocodiles, caimans, and turtles. The “model Emberá village” nearby is rather hokey, but it’s a chance to meet a few Emberá and buy their tightly woven baskets and other handicrafts.
There’s a small marina just outside Gamboa , near the one-lane bridge across the Río Chagres , where boatmen offer fishing tours on their basic pangas. Stop by at least a day ahead of time to work out a deal. Anglers need to be on the lake just before dawn; by midmorning the peacock bass stop biting. A morning of fishing costs about US$50. The captains can also take visitors on an exploratory cruise around Lago Gatún  and/or the Chagres River. The price depends on distance.
A group called Panama Canal Fishing (cell 6678-2653, www.panamacanalfishing.com ) offers a higher-end, all-inclusive fishing experience on Lago Gatún. Trips are made on a roomy and comfortable Hurricane Fundeck 201. Prices are US$395 per boat and include round-trip transfers between Panama City  and Gamboa, a fishing guide and captain, picnic lunch and drinks, and all fishing equipment, bait, and lures. Boats can accommodate up to six anglers, at US$20 extra per person after the first two. Prices do not include sales tax (currently 7 percent).
The Panama Canal Fishing is run by Richard Cahill and his wife, Gaby. Rich has worked for years as an accomplished naturalist guide with Ancon Expeditions, and I highly recommend him. He’s guided me around the Darién  jungle, not a fishing lake, but he’s knowledgeable, reliable, enthusiastic, fun, and an all-around good guy. He’s fluent in English and Spanish and can swear colorfully in both. The company also offers tours of the lake’s primate sanctuary and the Panama Canal , usually as an add-on to the fishing trip.
Aventuras Panama (tel. 260-0044 or 236- 5814, www.aventuraspanama.com ) offers rafting trips on the Río Chagres . The rafting is usually quite gentle, with mostly Class II rapids and a few Class IIIs. It’s not intended for those who need big white water. However, this is still a long, fairly rigorous trip and the Chagres, like any other powerful river, has seen its share of accidents and needs to be approached with respect. Clients are picked up from their hotel at 5 a.m. and driven into the highlands above Cerro Azul . From there, it’s a 1.5-hour hike through the forest to the put-in spot.
Rafters spend all day on the river, ending up in Lago Alajuela (also called Madden Lake) in the late afternoon. Clients are dropped back at their hotel around 7 p.m. The trip costs US$165 per person and includes breakfast, lunch, and transfers. Clients must be between the ages of 12 and 70. The company offers many other tours, including rafting trips on the Mamoní and Río Grande and a boat ride up the Chagres to visit the Emberá community of Parara Puru.
Unless the Canopy Tower Resort  is packed with guests, it offers day tours to anyone. There’s a decent chance of seeing good-sized mammals (other than your fellow visitors) and an excellent chance of spotting lots of birds. Possibilities include an early-morning (6:30–11 a.m.) or lunch (12:30–5 p.m.) visit for US$95 that includes a two-hour guided walk and wildlife viewing from the tower. An evening visit (5:30–9 p.m.), for US$85, includes dinner.