Set 2km south of the Medellín–Bogotá highway, three hours east of Medellín and five hours west of Bogotá, is the Reserva Natural Cañon de Río Claro, a small reserve/hotel. Here the crystalline Río Claro rushes through a stunning marble canyon surrounded by lush forest. Be sure to visit the Caverna de los Guácharos, a spectacular cave next to the river.
Bring a swimsuit, towel and flashlight. On weekends the reserve is often full of Colombian high-school students – you may prefer to come during the week. If staying overnight, don't even think of showing up without an accommodation reservation – you won't get in.
The reserve is 24km west of Doradal, where you will find a couple of budget hotels and internet cafes near the main plaza, as well as ATMs.