The Nazca Lines are one of the world’s greatest archaeological mysteries: hundreds of enormous geoglyphs carved into the desert plains of southern Peru between 500 BCE and 500 CE. These designs include geometric shapes, animals like monkeys, hummingbirds, and spiders, and even humanoid figures. Some are nearly 1,300 feet (400 meters) long, only fully visible from the air.

No one knows exactly why the Nazca people created them. Theories range from astronomical calendars to ritual pathways used in ceremonies, while others believe they were offerings to the gods. What is certain is their scale and precision are mind-blowing, especially considering they’ve survived for over a thousand years in the harsh desert climate.

Learning about the Lines made visiting them even more awe-inspiring. Whether seen from the air or from the viewing tower along the highway, they leave you with a sense of wonder, and plenty of questions.

If you’re not taking a flight, the Nazca Lines Viewing Tower is the easiest and most affordable way to see the geoglyphs. Located right off the Pan-American Highway, the 42-foot (13-meter) metal tower gives you an elevated look at several figures, including the Hands and the Tree. From here, you can really appreciate their scale and the mystery of how they were made.

Pro Tip: Combine a viewing (flight or tower) with the Maria Reiche Museum, dedicated to the German archaeologist who spent her life studying and protecting the Lines.