Lake Amatitlán lies 30 kilometers south of Guatemala City [1] on the road to The Pacific Coast [2]. The lake is in the process of being rescued from what would have been certain ecological death caused by wastewater from nearby industry and uncontrolled urban growth.
A new sewage treatment plant now filters the filthy waters of the Río Villalobos, which once flooded untreated sewage into the lake. Trees have been replanted and the lake is being pumped with oxygen and cleaned of plants in an effort to reverse its eutrophication. It’s still not possible to swim in the lake’s waters, though it may be some day.
You’ll probably need to rent a car to get to Lake Amatitlán, though you could also hire a cab to take you there from Guatemala City [1] for about $25.
If you’re driving, take the Pacific Highway (CA-9) south out of the city. The main entrance to the Amatitlán lakeshore is at Km. 26. You’ll see signs. The exit veers off from the right side of the highway. From the exit ramp, you’ll come to a Shell gas station, where you turn left. Follow the road until it dead-ends just past the soccer fields on your left. Turn left at the dead end. You’ll pass a bridge over the Río Michatoya on your right. The next left will take you to the Teleférico and farther up that same road is Parque Nacional Naciones Unidas [3]. Turning right onto the bridge over the Río Michatoya followed by an immediate right will bring you to the Santa Teresita hot springs.
Links:
[1] http://www.moon.com/destinations/guatemala/guatemala-city
[2] http://www.moon.com/destinations/guatemala/the-pacific-coast
[3] http://www.moon.com/destinations/guatemala/guatemala-city/near-guatemala-city/lake-amatitlan/recreation/parque-nacional-naciones-unidas