To go to Monteverde you have to get to the Panamericana Freeway. If you take a detour, you can get to the Cortes Waterfalls. They are on the way to Liberia (North).
This waterfall is off the tourist circuit, but in my opinion it is one of the most beautiful spots in the area. There is a small parking lot, where you can leave your car. From there, a five-minute walk will take you to the waterfalls. There is a small sandy beach where you can lie under the sun for a couple of hours and enjoy the sight of the waterfall. There is no entrance ticket. The water is warm. Definitely a great place to relax and go for a swim.