Bayfield Peninsula Sea Caves are some of the most jaw-dropping sights you can witness in the country. In the winter, they are morphed into ice caves. Take the entire family and explore their beauty. The incredible formations and the splendor of the crystal clear ice will astonish you. Spectacular year-round ice caves you can visit are Big Four in Washington, only a short drive from Seattle, and Mendenhall Glacier in Alaska. They are constantly on the move, as the glacier inches towards Mendenhall Lake and changes shape along the way.