Parque Nacional Volcán Tenorio

The park's heavenly blue river, waterfalls and lagoons are among the most spectacular natural phenomena in Costa Rica; as a result, the park is known to locals simply as Río Celeste (though it's officially named after the soaring 1916m Volcán Tenorio). From El Pilón ranger station at the park entrance, a 5km out-and-back hiking trail winds through the misty forest, taking in the park's highlights.