1st Reconnaissance Battalion is a reconnaissance battalion in the United States Marine Corps. It is a stand-alone battalion with no parent regiment. Instead, it falls directly under the command of the 1st Marine Division. 1st Recon Bn is located at Marine Corps Base Camp Pendleton in San Diego, California.

Marine Corps Base Camp Pendleton is the major West Coast base of the United States Marine Corps and is one of the largest Marine Corps bases in the United States. It is on the Southern California coast in San Diego County and is bordered by Oceanside to the south, San Clemente and Orange County to the north, Riverside County to the northeast, and Fallbrook to the east.