One hundred kilometres south of Machala, spread over a dusty, semi-arid river valley close to the Peruvian border, is the Puyango petrified forest, the largest of its kind in South America. It contains dozens of enormous fossilized tree trunks up to 120 million years old, many of which you can see from the 8km of marked paths wending through the mineralized wood. At the visitor centre, where you pay and register your visit, you can hire a guide (usually one of the warden’s sons) to show you around the site; they don’t speak English, but will point out many hidden fossils you’d otherwise miss, such as the imprints of ferns concealed by riverside plants. The most impressive relics are the giant tree trunks, types of araucaria, which grew in the region millions of years ago; many are in fragments but a few are almost whole, the largest being 11m long and 1.6m in diameter. The area is also inhabited by more than 150 species of birdlife, including beautiful red-masked parakeets.
A small museum (usually locked; ask the staff for entry) near the visitor centre houses a stash of incredible exhibits, including many marine fossils dating from when much of the region was covered by the sea, now 50km away. The collection includes fossilized pieces of fruit, including a chirimoya (a custard apple – you can still see the pips), a ray, small tortoise and octopus with clearly visible eyes. Perhaps the most intriguing pieces are the large, perfectly oval stones you can hold in your hands – and which the staff believe are dinosaur egg fossils.