Icicles are long, pointed formations of ice that hang from the edges of roofs, trees, and other structures during cold weather. They form when water drips from melting snow or ice and refreezes as temperatures drop. This process can create beautiful, shimmering structures that vary in size and shape. Icicles can pose safety hazards, as they may fall and cause injury or damage. It is important to be cautious around areas where icicles are present, especially during warmer days when they may begin to melt. Proper maintenance of roofs and gutters can help prevent the formation of large icicles.