About 20km east of Las Lajas, El Nancito is a small community known for its underwhelming rock carvings. Locals say that the carved boulders were made more than 1000 years ago, though no one really knows for sure.
From the Interamericana, turn north onto the road to El Nancito. After 3.5km, when you reach the ‘Museo' sign, turn left (west) and drive 100m until you come to rather large fenced-in boulders and the park's museum entrance. If taking public transportation, jump off any Interamericana bus at El Nancito, and then hike the 3.5km uphill to the boulders.