DENVER (AP) — A swath of U.S. forest land bigger than Rhode Island was closed in Colorado to help firefighters battle several wildfires and prevent new fires in tinder-dry terrain.

The U.S. Forest Service took action, citing the limited number of resources available to fight multiple fires. Fire crews faced high winds, low humidity and tinder-dry conditions as they tried to protect threatened structures and stem the growth of the northern Colorado fires, including one that's the largest in the state's recorded history.

Authorities say about 3,000 firefighters are battling roughly 690 square miles (1,789 square kilometers) of land charred by wildfires in north-central Colorado and southern Wyoming.