After arriving in San Jose (yes, we would have liked to have a flight from San Jose, to San Jose, but we got SFO to San Jose via Houston instead :D), and a night at hotel aeropuerto, we took our transport to Arenal.
Arenal is a geothermic area that's supposed to be a highlight in Costa Rica, but during the rainy season, it's obviously very rainy. That said I think for our group it just wasn't a highlight because we've all seen better volcanos and much better sceneries, but oh well...

We went to the volcano national park, but unfortunately the rain started and then got really bad, so we didn't see much and got pretty wet:

the path ended up with a stream that was almost knee-high

view wasn't great

The next day, we went on a kayak and mountain biking tour. Thankfully we only got light rain during the kayaking, but we didn't get to see many animals, outside of one at the parking lot:

Since we didn't get to see that much, we went to the Hanging Bridges Park where we took a naturalist guide to help us spot wildlife:

tarantula

Leafcutter ants are super cool. They cut and bring back leaves to their nest to cultivate a fungus which they eat afterwards.

the leafcutter ants worked hard :)

After our day, we got back to our room to enjoy the towel art :)

The third day, we had a hike to the top of a point where the volcano erupted, then collapsed, and is now filled with a big lake. Thankfully the rain stopped as we started our hike and we got decent enough views. The trail was very rough though and I'm not certain it's a must do hike, just an ok one:

did I mention the trail is bad?

After the hike, we went down to an impressive waterfall (especially with all the rain we had gotten). That one was worth the trip:

side waterfall

We then had a quick stop at La Fortuna to pick up our rental car to enjoy our towel art: