Ancient seas have left behind a variety of geological features that can be found in national parks throughout the United States. Some national parks that preserve ancient sea features include:
- Death Valley National Park in California, which contains fossilized sand dunes, ancient shorelines, and other evidence of ancient seas that once covered the region.
- Fossil Butte National Monument in Wyoming, which preserves an ancient lake bed that was home to a diverse array of marine life, including fish, turtles, and crocodiles.
- Badlands National Park in South Dakota, which contains layered rock formations that were formed by ancient seas and rivers.
- Dinosaur National Monument in Colorado and Utah, which contains a wealth of fossils, including those of marine reptiles and other ancient sea creatures.
- Florissant Fossil Beds National Monument in Colorado, which contains fossilized remains of ancient sea creatures such as fish and insects, as well as plants and trees that grew in the area during the time of ancient seas.
- Great Basin National Park in Nevada, which contains ancient sea fossils from the Permian period, and also Lehman Caves with ancient sea fossils formations.
These are some of the examples of the National Parks that contain ancient sea fossils and formations.