In the United States, what does a yellow diamond sign showing a black cross warn drivers about?

In the United States, a yellow diamond sign showing a black cross warns drivers about a crossroads ahead.

The symbol represents two roads crossing at an intersection. It is a warning sign, so it tells drivers to anticipate a junction and adjust speed or attention before reaching it; it does not itself assign right of way. Priority is controlled by traffic lights, stop or yield signs, road markings, or the applicable traffic law.

The sign belongs to the United States warning-sign system, in which warning signs are normally diamond-shaped and yellow with black symbols or lettering. A cross symbol should not be confused with the different symbols used for a railroad crossing, side road, or traffic signal ahead.

The warning is particularly useful where the junction may be hidden by a crest, curve, vegetation, or buildings. Drivers should look for turning vehicles, pedestrians, and cyclists as they approach. Additional plaques can provide information such as distance or the configuration of the intersection.