Federal enclave

Parcel of land which is within a state but under federal jurisdiction

In United States law, a federal enclave is a parcel of federal property within a state that is under the "Special Maritime and Territorial Jurisdiction of the United States". These enclaves are used for the many different functions of the United States federal government, and include post offices, arsenals, dams, road, etc., and usually are owned, secured and administered by the U S. federal government itself. The United States in many cases has received similar jurisdictional authority over privately owned properties which it leases, or privately owned and occupied properties which are located within the exterior boundaries of a large area as to which a state has ceded jurisdiction to the United States.

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