The Andes were formed by tectonic activity whereby Earth is uplifted as one plate (oceanic crust) subducts under another plate (continental crust). To get such a high mountain chain in a subduction zone setting is unusual, which adds to the importance of trying to figure out when and how it happened. However, the timing of when the Andean mountain chain uplift occurred has been a topic of some controversy over the past ten years. Now, new research shows that the Andes have been a mountain chain for much longer than previously thought.