Bouldering
Bouldering is a popular sport at the Ayo and Casibari Rock Formations near the famed Natural Bridge, in the center of the island. Like a Stonehenge that melted under the tropical sun, these mammoth, smooth, wind-sculpted boulders rise prehistorically from the desert floor up to 100 feet in height, providing a jungle gym for climbers. From the top, the view is a study in wet and dry contrasts.

Climbing the Haystack
Hooiberg, Aruba's most outstanding landmark, stands 541 feet (165m) tall and is known locally as the Haystack. It pokes out of the center of the island, between Santa Cruz and Oranjestad. Formidable steps - 582 in all - take climbers to the top. On a clear day, visitors can spot neighboring Venezuela.

Cunucu Safari
Known as semi-horseback-riding by locals, jeep safaris along the rutted, rocky dirt roads of Aruba's outback are slightly less strenuous than the real thing. Local guides lead you as you steer your own jeep-like vehicle from sight to sight, and through Arikok National Park. Most tours provide lunch and snorkeling on one of Aruba's beaches. If you're the solitary adventuresome type, you can rent your own jeep-like vehicle, which allows more flexibility. (Safari tours have agendas and insurance regulations that preclude exploration of some of the island's desirable attractions.)

Diving and Snorkeling
Several wrecks ring the island with intriguing dive sites. The most popular are the Antilla, 54 feet below, and the California (which failed to respond to the Titanic's distress signal), at 30 feet (9m) under the seas. Colorful reefs yield rich underwater marine life including lobsters and squid at Baby Be ach Reef (a shore dive), turtles and manta rays at Puerto Chiquita, seahorses at Magel Halto Reef, and green morays at Plonco Reef. Two miles long and one of the Caribbean's prime underwater sites, Barcadera Reef allows you to float through a forest of sea fans. The most recent Aruba diving trend, kayak diving, strives to protect the fragile reefs.

Gambling
Aruba is one of only a handful of Caribbean islands that offer exciting gambling opportunities. All traditional casino games, including craps, roulette, black jack, baccarat, seven-card stud, and Texas Hold'Em are available at Aruba's gambling spots. Other favorites include Caribbean Stud Poker, which was born right here in Aruba, and, of course, slot machines. The island's main casinos include the Alhambra Casino and Aladdin Theatre, which is Aruba's busiest; the Casablanca Casino in the Hilton Hotel; the Crystal Casino at the Sonesta Hotel; and the colorful Royal Cabana Casino at the La Cabana All-Suite Beach Resort.

Horseback Riding
Horseback riding across the cunucu (outback) gives visitors a feel of what Billy the Kid must have experienced in the Arizona desert. Several outfitters can put you on horseback to venture into different areas of the rugged countryside, including Arikok National Park. Other tour operators organize rides that head for the Natural Pool, an out-of-the-way, prime swimming spot on the northern coast.

Windsurfing
Aruba's stiff and constant winds, which average a speed of 21mph (34kph), have earned the island a reputation among flat-water sailboarders. Hadikurari Beach at Fisherman's Huts on the west coast, site of the annual Hi-Winds Pro Am Windsurfing Competition, is one of the best windsurfing spots. Other popular windsurfing beaches include Boca Grandi and Bachelor's beaches on the northeast coast. Windsurfing shops, rentals, and instruction are plentiful at hotels and other locations.