Since Mombacho Volcano is technically closed on Mondays and difficult to get too by public transit we decided to do an organized our. Ride up the the volcano was nice enough, and one at the top it was refreshinly cool. The biological center is decent enough but not really all that informative. We did the smaller loop hike at the top, nice views of Las Islestas being the highlight. The fumaroles are a bit of a letdown however as it's a hole in the ground with some steam coming out. The longer Puma trail may have been more interesting and have a better chance to see wildlife.
On the way down we stopped at a coffee plantation for a tiny cup of coffee and a bunch of beans in various stages on the table. No explanation or tour of the plantation itself, although they did give each of us a pound of coffee.
Bottom line is Mombacho Volcano is worth visiting, but do it on your own and hire a guide at the biological station. If you're set on doing a tour choose wisely and ask lots of questions.
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