The beauty of a hanok is not just aesthetic; it is a masterclass in environmental engineering. Look up at the roofs, known as Giwa. Notice the Cheoma, those deep, sweeping eaves that tilt upward like the wings of a crane. These were designed to perfectly calculated angles: during the hot summer, they block the high sun to keep the rooms cool, but in winter, they allow the low sun to reach deep inside to provide natural warmth. Every house is built using four natural materials—wood, earth, stone, and Hanji, a traditional paper made from mulberry trees that covers the windows. But the real secret is beneath your feet. Koreans perfected Ondol, a system of underfloor heating using smoke from a kitchen fire to warm up stone slabs under the rooms. This is balanced by the Maru, a raised wooden floor open to the courtyard that encourages air circulation during the humid summer. It is a house that breathes with the seasons, harmonizing perfectly with the natural landscape of mountain and valley.