In most counties in the United States, the local trial courts conduct their business in a centrally located courthouse which may also house county governmental offices. The courthouse is usually located in the county seat, although large metropolitan counties may have satellite or annex offices for their courts.
In some cases this building may be renamed in some way or its function divided as between a judicial building and administrative office building. Many judges also officiate at civil marriage ceremonies in their courthouse chambers. In some places, the courthouse also contains the main administrative office for the county government, or when a new courthouse is constructed, the former one will often be used for other local government offices. Either way, a typical courthouse will have one or more courtrooms and a court clerk's office with a filing window where litigants may submit documents for filing with the court.
Each United States district court also has a federally owned building that houses courtrooms, chambers and clerk's offices. Many federal judicial districts are further split into divisions, which may also have their own courthouses, although sometimes the smaller divisional court facilities are located in buildings that also house other agencies or offices of the United States government; some branches of federal courts are even housed in rented office space in buildings housing commercial tenants (for instance, the United States Bankruptcy Court for the District of Delaware is located in an office building in Wilmington across the street from the main courthouse of the District Court).  The United States District Court for the Eastern District of California has a courthouse in Yosemite to hear misdemeanors and petty crimes for Yosemite National Park.
The courthouse is part of the iconography of American life and is equivalent to the city hall as the symbol of the municipium in European free cities. Courthouses are often shown in American cinema (i.e. "Peyton Place", "Back to the Future", and "My Cousin Vinny"). They range from small-town rural buildings with a few rooms to huge metropolitan courthouses that occupy large plots of land. The style of American architecture used varies, with common styles including federal, Greek Revival, neoclassicist, and modern.
Due to concerns over potential violence, many courthouses in American cities often have security checkpoints where all incoming persons are searched for weapons, normally through the use of an X-ray machine for all bags and a walk-through metal detector, much like those found at airports.
For example, the Los Angeles Superior Court added such checkpoints to all entrances to its main courthouse in Downtown Los Angeles after a woman was shot and killed by her ex-husband in open court in September 1995. The Supreme Court of California ruled in 2002 that Los Angeles County (which at the time was responsible for maintaining the courthouses) was not liable to her three children under the California Government Tort Claims Act.
After the Oklahoma City bombing, the federal government proceeded to heavily fortify all large federal buildings, including many urban courthouses.
Some courthouses in areas with high levels of violent crime have redundant layers of security. For example, when the Supreme Court of California hears oral argument in San Francisco or Los Angeles, visitors must pass through one security checkpoint to enter the building, and another to enter the courtroom.