Last updated: April 28, 2025
Most people who visit La Fortuna, Costa Rica go to see Arenal Volcano, the famed cone-shaped giant that put this sleepy agricultural town on the map. But there’s another intriguing sight nearby. Cerro Chato is a lesser-known volcano that sits unassumingly right next to Arenal. Although Cerro Chato is dormant, it has a stunning emerald green crater lake that looks almost out of this world. The trek up to the lagoon is one of the more challenging hikes in Costa Rica, but there is some important information you should know before attempting it.
Accessing Cerro Chato
Cerro Chato is located to the west of the town of La Fortuna. Though quite a few miles away, its green forested outline is visible from the downtown alongside Arenal Volcano. In the past, the most common access points for Cerro Chato were the Green Lagoon Lodge and Arenal Observatory. When we visited many years ago, we opted for the Observatory because at the beginning of the hike there are fantastic views of Arenal Volcano. We also wanted to check out the Observatory’s many other trails, its hanging bridge, and small waterfall.
IMPORTANT UPDATE : The government closed off access to Cerro Chato in 2017 but that hasn’t stopped people from continuing to visit. Adventurous hikers still enter from the Green Lagoon Lodge, where they purchase a ticket to explore the lodge’s trails. The Cerro Chato trail (unofficial) is off of that loop and quite difficult and dangerous. We have heard reports that it can take 4+ hours roundtrip and is very treacherous. If you have done this hike, let us know how it was in the comments below.
Tip: If you are looking for a challenging hike in the La Fortuna area, we really liked the Ultimate Jungle Hike. It’s a guided tour to a small reserve that has a waterfall, swimming hole, and some steeper, tougher trails (but not as crazy as Cerro Chato). After the tour, they bring you to a local place to help cook a traditional lunch.
The Hike From Arenal Observatory (now closed)
Note: While this information is from several years ago, you can still learn a lot about the conditions on the mountain. It sounds like not much has changed.
Our hike up to the top of Cerro Chato from the Arenal Observatory (now not permitted) was about 2 hours each way. It’s was strenuous trek that was definitely not for everyone. Much of the trail was narrow and steep, with bulging tree roots to avoid and some slippery spots due to clay. The scenery was gorgeous, however, beginning in the lowland rainforest typical of the area and ascending into sometimes misty, higher altitude cloud forest.
Once we reached the highest point of Cerro Chato (1,140 meters or 3,740 feet), we had to do even more hiking to get to the crater lake. But at this summit was where you could get the best views of the green lagoon (see cover photo above).
To get down to the lake, it was about another 20 minutes but very difficult. The extremely steep, haphazard path was more like a scramble than an ordinary hike. We have heard this is true from the current access points too.
At times, it was difficult for us to get our footing as there was no place to step and no ropes to help guide us. This forced us to maneuver with our hands and cling onto roots and trees when necessary. We did make it down but saw lots of others turn around.
Tip: If you attempt this hike, be sure to wear clothes and footwear that you don’t mind getting dirty. The entire trail is clay and the final portion can be very muddy, especially if it has rained recently. You’ll also need plenty of food and water.
If you do make it to the bottom, you’ll get to enjoy the lagoon from a new perspective. Along the shore of the small beach area, you can appreciate the breadth of the lake and see the moss-covered greenery along its edges close up. If you’re in need of a cool down, you can also swim in the emerald water, though it was a bit too green for our taste.
Best Times to Visit Cerro Chato
The best time to hike Cerro Chato is during the driest months. In La Fortuna that usually means mid-August to mid-November. The trail shouldn’t be as muddy this time of year and the lagoon shouldn’t be fogged in and invisible, as it sometimes is during other months.
What to Wear/Bring
- Hiking boots with good gripping treds and ankle support
- Trekking poles or a walking stick
- Insect repellent
- Plenty of water as it can be extremely hot and humid
- Snacks (you may be out there for a while!)
- First Aid Kit
Check out our Daypack Essentials post for a full list.
Cost
$15 from Green Lagoon Lodge (for access to their trails). You will need to enter un unauthorized trail to access Cerro Chato.
Conclusion
If you’re looking to do the Cerro Chato hike in La Fortuna, our advice would be to skip it. This is an unauthorized hike and it can be very dangerous. We were lucky to visit Cerro Chato years ago when the trails were still open and more regularly used. These days, we’d recommend doing some of La Fortuna’s other awesome activities. For a comprehensive list, see this post.
Have something to share about the Cerro Chato Hike? Leave a comment below.
Looking for more information to help you plan? Check out these pages:
Ultimate Jungle Hike – This is a tour we offer in the La Fortuna area. It incorporates a challenging hike, dip in a peaceful pool/waterfall, and a short cooking class with lunch.
Hanging Bridges in Costa Rica: Where to Go for the Best Experience – Wondering which hanging bridges to go on and where? This article covers the major places to cross hanging bridges in Costa Rica and points out our favorites.
Ecotermales Hot Springs – After a hard hike, our advice is to soak in the naturally heated springs at night. This is one of our favorite spots.
