The phrase "interesting rock formations" refers to natural structures or patterns created by rocks that are visually appealing and captivating. These formations can be found in various locations such as cliffs, mountains, quarries, and beaches, among others. They often result from geological processes like erosion, weathering, and volcanic activity, which shape the earth's surface over time. The phrase is commonly used to describe landscapes or scenery that are visually striking due to their unique rock formations.