Atlas Obscura
Poás Volcano in Alajuela, Costa Rica
Poás Volcano National Park contains the world's largest open volcano, complete with a vibrant greenish-blue to yellow volcanic lake that bubbles and boils. Poás is located within a beautiful and lush Central Conservation Area of central Costa Rica that encompasses 6 National Parks and many protected areas. Birds flutter through the heavily vegetated area, including the rare resplendent quetzal,…