Lake Arenal, Alajuela & Guanacaste, Costa Rica

Also known as:  Lago Arenal, Laguna de Arenal

Welcome to the ultimate guide to Lake Arenal — things to do, where to stay, fun facts, history, stats and more. Let’s dive in!

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Looking for Lake Arenal cabins or other accommodations? Save time and use this interactive map to find, compare and book at the best rates. Or explore our comprehensive list of favorite travel partners.

All About Lake 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
  • Fishing
  • Boating
  • Swimming
  • Canoeing
  • Kayaking
  • Whitewater Rafting
  • Hiking
  • Spelunking
  • Waterfall
  • Wildlife Viewing
  • Birding
  • National Park
  • Ruins

Fish Species Found at Lake Arenal

  • Bass
  • Catfish
  • Guapote
  • Machaca
  • Mojarra
  • Rainbow Bass
  • South American Bass
  • Tilapia

Find Places to Stay at Lake Arenal

If you’re considering a Lake Arenal lake house rental or hotel, we’ve made it super easy to find the best rates and compare vacation accommodations at a glance. Save time using this interactive map below.

Recommended Sites to Book a Lake Arenal Vacation

If you want to take a deeper dive to find waterfront lake cabins, cottages, condos, hotels or resorts, check out our favorite Lake Arenal lodging partners.

  • VRBO – Use VRBO to find the perfect lake rental home, condo, cabin, cottage or other vacation property.
  • – One of the world’s leading digital travel companies, connects travelers to everything from cozy B&Bs to luxury resorts.
  • Expedia – Expedia is a popular online travel agency with more than 140,000 lodging properties worldwide.
  • – With more than 325,000 hotels in 19,000-plus locations, is an industry leader in online accommodations.
  • TripAdvisor – Read traveler reviews and compare prices on hotels, vacation rentals and more at TripAdvisor.
  • Trivago – Trivago helps travelers compare deals for hotels and other accommodations from a variety of booking sites.
  • KAYAK – KAYAK scours hundreds of other travel websites at once to find the best deals on hotels and other travel-related services.
  • RVshare –RVshare connects travelers interested in renting a motorhome with owners who have RVs to rent.
  • CampSpot – Campspot offers premier RV resorts, family campgrounds, cabins and glamping options across North America.

Note: These are affiliate links so we may earn a small commission if you book through them. While there is no extra cost to you, it helps provide resources to keep our site running (thank you)! You can read our full disclosure policy here.

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

We strive to keep the information on LakeLubbers as accurate as possible. However, if you’ve found something in this article that needs updating, we’d certainly love to hear from you! Please fill out our Content Correction form.

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