First, so nobody oversells it: Arenal has not produced lava since 2010. If you come expecting to watch the crater spit at night, you will be disappointed. What you do get is a near-perfect 1,670-metre cone, and forest reclaiming the lava flows from the 1968 eruption.
What time
Morning. Almost every day it wakes up clear and clouds over after noon. In green season, earlier still. This is the only rule that really matters.
Where
Arenal 1968 has the trails that run across the eruption''s lava flows. It is the only way to see up close what the lava did and how the forest is taking it back. There is a lagoon with the volcano behind it that is the classic shot.
Mirador El Silencio is the view without the long walk, if you just want to see it and go.
And if you head to Lake Arenal, the road around it gives you the cone from the other side.
What to expect
- A clear cone: depends on the day. Nobody can promise it.
- Lava: no. It has been dormant since 2010.
- Wildlife: on the trails, coatis, monkeys and toucans if you are lucky.
- Heat: the trails are open. Hat and water.
The national park
Arenal Volcano National Park has its own trails and its own entrance. It is a separate place from the private viewpoints, with its own hours.
After the walk, the obvious ending is the hot springs: the same volcano you just looked at is what heats that water. See also what to do in three days.