This is the best volcano in CR where you can see its cone shape. Went here for 2 days. First day np itself. Did 3 hikes. 1 from 4km or so, round trip. You can see a lot of lava rocks, the volcano itself and lake arsenal. Nice trail, didn't see much wildlife. 1 trail of 1 km. ok trail, lots of lizards. And we walked up to a nice view point (also reachable by car) of the volcano in its full beauty.
Second day we went to the np, only then at the observatory lodge entrance (little bit further). Did a couple of hikes here as well. Again nice view points of arsenal volcano and chato volcano. Climb chato volcano to the top to see the lake in the crater. Difficult/hard climb! Also walked to the hanging bridge, waterfall and old lava stream. Saw a coral snake..!! Nice hiking day as well. Didn't see too much wildlife here as well, but nice views on the trails.
You can do some mountain biking in the area as well.
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