Lake Arenal, Alajuela & Guanacaste, Costa Rica
Also known as: Lago Arenal, Laguna de Arenal
Lake Arenal, flanked by lush rainforest and the magnificent Arenal Volcano, is a world-class destination lake. Known for its feisty rainbow bass and incredible winds, the lake is a favorite among anglers, windsurfers and sailboarders. Nearby La Fortuna, known as the adventure capital of Costa Rica, adds to the mix cave spelunking, bungee jumping, whitewater rafting, canopy (zip-line) tours, and waterfall rappelling. Yet Lake Arenal’s daring spirit is tempered by groomed hiking trails, wildlife watching (monkeys included), and spectacular scenery, making it an ideal lake for both a low-key vacation and high-adrenaline adventure.
At 21,128 acres — three times its original size — Lake Arenal is Costa Rica’s largest lake. Known locally as Lago Arenal or Laguna de Arenal (Arenal Lagoon), the reservoir sits at the base of Arenal Volcano. In 1968, after 400 years of dormancy, Arenal Volcano awoke with a violent eruption, destroying several towns including the original Arenal and Tabacon. Today, their ruins are flooded beneath Lake Arenal, which was expanded in 1979 to generate hydroelectric power and drinking water. The reservoir is the golden child of Costa Rica’s hydroelectric power program; Lake Arenal generates more than 70% of Costa Rica’s hydropower – and 50% of the country’s electric power.
Straddling the provinces of Alajuela and Guanacaste, Lake Arenal is an aquatic paradise, attracting lake lovers from around the globe. Lake activities include swimming, kayaking, canoeing, boating, windsurfing, and fishing. In fact, Lake Arenal is recognized internationally as a mecca for inland anglers, and offers opportunities for solo and group fishing trips. Rent a boat and test your fish-finding skills, or hire one of Lake Arenal’s experienced fishing guides. You’ll troll for the world-famous and sharp-toothed guapote (rainbow bass), an incredible fighting fish that can exceed 15 pounds. Beneath the lake’s sparkling surface, rainbow bass are joined by populations of machaca, mojarra, catfish, South American bass, and tilapia.
In addition to fishing, Lake Arenal is well known for its excellent windsurfing and sailboarding. The reservoir’s average water temperature hovers at 72 degrees year-round, though ideal sporting conditions are from November through April, when high winds kick up around the lake. Beginner and advanced windsurfers will benefit from the lake’s boarding culture: experienced professionals offer lessons, gear rental, and plenty of camaraderie.
Surrounded by waterfalls, volcanic hot springs, caves, tropical rainforest and a picturesque, cone-shaped volcano, the Lake Arenal area is also ideal for exploration on foot. Hanging bridges offer a birds-eye view of the blue waters and startling Arenal Volcano cone, while private reserves around the lake form a web of hiking trails that pass near the reservoir’s shoreline. Outdoor aficionados, wildlife lovers, and birdwatchers are especially fond of Arenal Volcano National Park. The 30,000-acre park hosts pre-montane forest, lowland rainforest, cloud forest, and several other ecosystems. Common sighings include toucans, woodpeckers, coatimundis, howler monkeys, and sloths.
After a long day of hiking, fishing, or windsurfing on Lake Arenal, there’s nothing better than a relaxing dip in natural volcanic hot springs. Just a few miles west of the lake, several commercial hot springs promise gorgeous settings, varying water temperatures, and natural springs known for their healing powers. And when the sun goes down, tourists gather at the base of Arenal Volcano to watch the iridescent lava show; October is the best month for lava viewing.
Local lore has it that Lake Arenal is home to a 100-foot lake monster, though this cow-headed, horned, and serpentine beast is rarely seen and never photographed. Nearby Cote Lake, also called Lake Coter, is a mystical volcanic crater lake just west of Nuevo Arenal. The small lake, which boasts an excellent view down to Lake Arenal, is known for several UFO sightings, including one that was photographed by NASA.
After an exciting day, there’s no better place than your vacation rental’s lakeview porch. Lake rentals and real estate take advantage of the lake terrain, and are often perched atop green hills that overlook spectacular views. For a more urban setting, the town of La Fortuna (population approximately 7,200) is located a few miles east of the lake and provides a variety of tourism services, including hotels and bed and breakfasts. Tilaran, a small city of approximately 8,300 residents, is located four miles south of Lake Arenal’s western end. On the lake’s northern shore, between these two population centers, lies the picturesque town of Nuevo Arenal. Other small towns around Lake Arenal, like Aguacate, Las Piedras, San Luis, and Tronadora, are less populated.
With blue waters and even bluer skies, Lake Arenal is the sapphire jewel of Costa Rica. Excellent adventure activities, outdoor fun, and vacation opportunities await the thousands of tourists who visit each year. And for those looking for a Costa Rican home away from home, Lago Arenal has a growing expat population and booming retirement communities — so come find your vacation house, investment property, or retirement home today.
Things to do at Lake Arenal
- Vacation Rentals
- Whitewater Rafting
- Wildlife Viewing
- National Park
Fish species found at Lake Arenal
- Rainbow Bass
- South American Bass
Lake Arenal Photo Gallery
Lake Arenal Statistics & Helpful Links
Lake Type: Natural Freshwater Lake, Dammed
Water Level Control: Instituto Costarricense de Electricidad (ICE)
Surface Area: 21,128 acres
Shoreline Length: 50 miles
Normal Elevation (Full Pond): 1,785 feet
Average Depth: 92 feet
Maximum Depth: 200 feet
Water Volume: 1,945,711 acre-feet
Completion Year: 1979
Lake Area-Population: 20,000
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