250 million years in the making — meet Seongryu Cave 🪨💎 Nicknamed the “Underground Geumgangsan,” this natural limestone cave in Uljin is packed with jaw-dropping formations and hidden chambers that feel like nature’s own art gallery. From the Three Buddhas in Chamber 11 to the sparkling Treasure Island in Chamber 12, every turn is a visual surprise. And the best part? It stays a cool 10–17°C inside all year round — perfect for beating the summer heat. Especially popular with photographers, the Piam Tunnel — which leads to the entrance of Seongryu Cave — is a hidden gem in itself. Its unique, almost otherworldly structure paired with the scenic views framed by the tunnel make it a must-stop photo spot 📸🌿 🪨 Seongryu Cave (성류굴) 📍 221 Seongnyugul-ro, Geunnam-myeon, Uljin-gun, Gyeongbuk 🕘 Hours Mar–Oct: 9AM–6PM Nov–Feb: 9AM–5PM (Closed Mondays, except during peak season) 💸 Admission Adults ₩5,000 / Teens & military ₩3,000 / Kids ₩2,500 / Seniors ₩1,000 Free for preschoolers & s...