The Rincon de la Vieja National Park is one of the most unique in Costa Rica, because it features a neat combination of rainforest and volcanic activity-observation at the same place. This 14,000 hectare park (36,000 acres), is just about 25km from the town of Liberia (and the Liberia International Airport); and its volcano stands about 1,895 meters (6,400 ft.) above sea level. This active volcano is constantly making minor eruptions, being the last in 2016, when some material was flowing down the mountain towards the North-eastern flank (mainly water and mud, nothing major).
People visit this park for numerous reasons, not only because of the amazing views that it has, but also for the many things that it offers while you are there, for example: as you are walking though the trails you can come across some places with bubbling water, mud pots, or “mini volcanoes”, which could be a very interesting experience during your vacation in Costa Rica, especially because these observation points are located inside of a lush rainforest! There is also natural hot springs along the trails, but these can only be observed because of the extremely high temperature they have. However if you are looking to freshen up, the Rincon de la Vieja National Park has numerous beautiful waterfalls where one can relax and swim under the canopy of the lush rainforest.
The climate in this particular area of Guanacaste is very unpredictable, because it gets the influence of the Pacific weather, as well as the Caribbean weather. To use a simple example, during the dry season of Guanacaste (November through May), it could be drizzling at this park, because the volcanic buildings of the Rincon de la Vieja National Park are actually the division point of the 2 weather influences (and an important factor to have Pacific and Caribbean weather), therefore, it could be raining here while is completely dry in the rest of the Guanacaste lowlands.
In the year 2011 the Rincon de la Vieja Volcano made an eruption (this was the awakening point after many years), it did not causing any major damages, but due to this eruption the main crater is off limits and cannot be climbed until today. However, as you are taking a hike in one of the trails around the volcano, you can see some mini craters that have geothermal energy with active felsic lava bubbling; as well as many fumaroles that can be seen everywhere you look.
Along the skirts of the volcano, many touristic activities take place, such as zip lining, horseback riding, waterfall rappelling, river tubbing and depending on the location, some river rafting. There are also nature walks in various places, where the visitors can learn about the flora of this region, and depending on your luck, some animals could be observed, being the most common the howler monkeys, white faced capuchin monkeys, spider monkeys, coatimundis, toucans, agoutis, pacas, and several species of birds.
The Rincon de la Vieja Mountains also offer a few hotels, but most of them are rustic-basic accommodations with an all-inclusive meal package, since there is not a lot of development yet around this region (the only restaurants found close to the National Park area are the ones inside the hotels).
Overall this is a beautiful place to visit, even if is just on a one day tour, especially for those tourists who decide to stay at the very dry area where the beach resorts are located; the Rincon de la Vieja National Park could be a truly nice-green oasis to admire the green nature Costa Rica is famous for.