I am currently on a 5 day trip beginning with Arenal Volcano, then Poas Volcano, then Turrialba and finally back to Irazu. Arenal is the most beautiful volcano...especially if you stay at the Volcano Observatory Lodge which is on the side where the most recent lava flows occurred, yet the Poas overlook and the nearby lake which is in an extinct crater of Poas make it the best value if you have time for only 1 volcano experience. The Hotel Altura is only 5 minutes from the summit which makes an ideal beginning each morning because there is no struggle to get there. Make sure you get to Poas as soon as it opens around 8 AM...the sky is usually clear and the many tour buses have not arrived. By 10:30 the place is an ant hill. They have a nice restaurant with snack food and good coffee, hot chocolate (make sure you get choco/leche) and expresso.
This is one of the best value attractions in Costa Rica because the $10 admission per person and $3 parking is very reasonable for the unique quality of the attraction.
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