The U.S. Navy base at Sugar Grove, Pendleton County, was part of the Navy Information Operations Command. The base mission was officially described as "communications research and development for the U.S. Navy, the Department of Defense and various elements of the U.S. government." The Sugar Grove facility also functioned as an electronic listening post for the National Security Agency, according to press reports concerning NSA documents leaked by former NSA contractor Edward Snowden in 2013. The Navy decommissioned its base at Sugar Grove in 2015, but NSA operations continued at another part of the facility.

The remote Sugar Grove site was selected in 1955 with the initial intention of building a 600-foot radio telescope for astronomical studies. A 60-foot dish antenna was completed in 1956. Work began on the foundation of the larger radio telescope in 1958, but the project was judged to be obsolete before its completion. Work was halted in 1962, and the 600-foot telescope was never finished.

A new purpose was found for the Sugar Grove facility when the Navy proposed that the site be used as a radio receiving station. In 1963 a naval radio station was established at Sugar Grove. The base lies within the radio quiet zone encircling the National Radio Astronomy Observatory at Green Bank in neighboring Pocahontas County. Sugar Grove benefits from the improved listening environment provided by the quiet zone and from the isolation provided by the surrounding mountains. The station initially relied on two 1,000-foot circular arrays of antennas, later removed. In 1968 work was finished on a 150-foot parabolic antenna, which remains the largest dish antenna at Sugar Grove, and in the same year the Naval Security Group established a detachment at the site. NRS Sugar Grove was commissioned on May 10, 1969. The Navy received communications from around the world at Sugar Grove.

Increased automation of naval communications brought the closing of the naval radio station in 1992, and the Naval Security Group Activity Command was established at Sugar Grove. In December 2005, the Naval Security Group Activity Command was replaced by the Navy Information Operations Command, which remains Sugar Grove's official designation.

The Sugar Grove naval base included two major installations. A lower support base along the highway near the community of Sugar Grove housed the administrative, lodging, dining and recreation areas. A smaller operations base at a higher elevation, code-named Timberline, included a variety of antennas and an underground operations building.

Sugar Grove's role in National Security Agency interception of international communications was revealed in newspaper reporting of the Edward Snowden controversy of 2013-14. In January 2014 the Charleston Gazette cited New York Times and Washington Post reports that Sugar Grove was part of a worldwide network of facilities engaged in monitoring satellite communications, including cell phone traffic. The Gazette also cited research by author Matthew Aid indicating that Sugar Grove's Timberline was paired with a similar listening station in England to intercept signals from satellites in stationary orbit over the Atlantic Ocean.

In April 2013 the Navy announced plans to close the facility by September 30, 2015. Senators Joe Manchin and Jay Rockefeller led discussions about turning the facility over to the state for use as a prison, but Governor Earl Ray Tomblin, citing the cost of the conversion and the annual expense of operation, declined to accept the facility. A Kansas company expressed interest in turning the base into a community college.

The Navy decommissioned the support base as scheduled, then put it up for online auction in February 2016. On July 25 it sold to an anonymous bidder who could not complete the purchase, and the facility was scheduled to be sold again through the traditional government bid process. In December the General Services Administration announced the sale of the base to Robert Pike, who will work with Mellivora Partners of Birmingham, Alabama, to convert the base into a health care campus for active-duty military personnel and West Virginia residents.

The associated antenna base was not closed and not put up for auction, and according to news reports continued to be operated by the National Security Agency.