In most states some portion of beaches are public land and all members of the public have a right to use that portion of the beach. The ability to walk along the beach is known as lateral beach access.

But the land between where people can park or walk to the beach and where they can enjoy the beach is often private property, making it difficult to provide access to the public while protecting personal property rights. The ability to reach the beach is known as vertical beach access.

Laws regarding public access to beaches vary from state to state but many states recognize the public trust doctrine, a legal doctrine that certain natural resources such as beaches are owned or held by the government in trust for the public’s use and enjoyment and that the government has an obligation to protect and maintain these resources for the public.

In Montana, the public trust doctrine applies, ensuring that certain natural resources, including rivers and lakes, are held in trust by the state for public use and enjoyment. While Montana does not have ocean beaches, it does have lake and river shores that are subject to public access laws. The state maintains that the public has a right to access these bodies of water, including the right to use the waters and the adjacent state-owned land up to the high-water mark for recreational purposes such as fishing, swimming, and walking. However, the land beyond the high-water mark may be privately owned, and access to the water through private land requires landowner permission. Montana law tries to balance public access to these natural resources with the rights of private property owners. Vertical access, or the ability to reach these shores, can be limited by private property, and in such cases, the public may need to use designated public access points or obtain permission from landowners to cross their land.