Western Union’s microwave relay terminal in Washington, D.C.

Situated at nearly 400 feet above sea level, Tenleytown has the District’s highest elevation and some of the region’s most significant and contested radio architecture and engineering structures.

Tenleytown Heritage Trail signs were recently installed in the neighborhood. The sign at the corner of Brandywine and Wisconsin features the neighborhood’s prominent radio history resources, including nearby radio and television studios and broadcast towers.

One of the most important historic buildings featured in the trail sign is the former Western Union Telegraph Company’s microwave relay terminal located one block away on 41st Street NW (shown at right with of the Heritage Trail signs in the foreground).

Built just after the end of World War II, Tenleytown’s Western Union building and tower became part of an elaborate Cold War telecommunications network that blurred the lines between the public and private sectors. Along with the Western Union building and tower, Tenleytown’s urban antenna farm also played a critical role in federal continuity of government plans in the event of a nuclear attack.

Western Union Telegraph Company building, 2002.

There have been communications towers in North America since the turn of the 19th century when optical telegraphy was introduced from France to American port cities. These early facilities were modest twenty to thirty-foot structures from which flags and other signaling devices were used in line-of-sight systems to communicate in code.

Civil War signal Tower. Library of Congress photo.

In 1844, Samuel Morse built the first successful electrical telegraph line laying the groundwork for a network of 30-foot poles that would mark the margins of roads and railroads throughout the nation before the end of the century. By the time Guglielmo Marconi successfully demonstrated his wireless communications system in 1899, the horizons of most U.S. cities were marred by a visual cacophony of electricity, telephone and telegraph wires and poles.

Marconi’s wireless unbound communications from an infrastructure strung together by cables and wires. For the first two decades of the twentieth century, amateurs, the government, and inventing entrepreneurs raced to build wireless stations with increasingly higher antennas to reach and receive more distant points. Radio, which combined the technological achievements of telephony and wireless telegraphy, rapidly spread across the nation in the 1920s bringing with it taller towers in greater numbers.

WJSV (now WTOP) radio towers in Wheaton, Maryland. Library of Congress photo.

With the proliferation of towers and antennas came complaints that towers adversely affect scenic and cultural resources while also reducing property values and interfering with existing radio and later television reception.

One early complaint documented in the media came in 1944 when NBC’s Blue Network proposed building a 250-foot tower in suburban Fairfax County, just across the Potomac River from Washington. Residents mounted a vigorous opposition effort because they believed the tower would “reduce the value of their property and desecrate the historical landmark Langley,” wrote the Washington Post in June 1944.

Four years later, another proposed Arlington tower — this time a 400-foot television tower — spurred residents into action with concerns that the structure would “spoil the beauty of a distinctively residential area.

In March 1945 the Federal Communications Commission (FCC) authorized the Western Union Telegraph Company to place into service an experimental microwave relay system between New York, New York and Philadelphia, Pennsylvania. The system to beam telegrams between stations used radio frequencies that had previously only been used by military radar systems.

WUTCo System Map

Western Union Telegraph Company microwave system map. Map by David Rotenstein, 2010.

The experimental system that used unattended stations placed at regular intervals to facility a line-of-sight radio relay allowed Western Union to refine the radio beam telegraphy process by improving its equipment to maintain constant signal strength. The equipment used in Western Union’s experiments was made by the Radio Corporation of America (RCA) under license to Western Union. The company’s goal was to develop a system that increased the capacity for sending telegraphs, to eliminate much of the company’s wireline reliance (i.e., make poles and wires obsolete) and to position it for providing transmission services for emerging television technology.

Image from a 1948 Western Union Telegraph Company annual report.

Western Union designed its system by incorporating two facility types: terminals and relay stations. In March 1945 the FCC authorized the Western Union to place into service an experimental microwave relay system between New York, New York and Philadelphia, Pennsylvania. This network linking New York and Philadelphia included terminals in Philadelphia and at the company’s New York City headquarters. Relays were planned at Bordentown, Ten Mile Run, and Woodbridge, New Jersey. The New York-Washington-Pittsburgh network incorporated the New York headquarters, a rooftop location in downtown Pittsburgh, and a new tower building for the Washington, D.C., terminal. Each terminal was connected by nodes in the network: unattended relay stations with towers and equipment buildings.

Art Deco Market Street Bank building, Philadelphia. Western Union placed its microwave antennas on the roof of this center city building opposite city hall.

While conducting the tests on the New York and Philadelphia system, Western Union applied to the FCC to construct a fully functional radio relay triangle between New York, Washington, DC, and Pittsburgh, Pennsylvania. On 7 November 1945, the FCC granted Western Union a “Radio Station Construction Permit” to build its facility at:

41st Street, near Wisconsin Avenue … to communicate with experimental stations of the permittee as necessary for development of commercial point to point radio communications between New York City, New York, Pittsburgh, Pennsylvania, Washington, D.C., and Philadelphia, Pennsylvania, (via intermediate relay stations).

Western Union was able to place rooftop antenna installations on existing buildings for its New York, Philadelphia, and Pittsburgh terminals. In Washington, however, the company required a new facility in the District’s highest-elevation neighborhood, Tenleytown. The site had been recognized since the 1920s as a prime location for broadcasting. Earlier efforts to construct a radio tower in the vicinity of the parcel Western Union sought failed when local residents in 1940 successfully blocked the approval by the District of Columbia’s Board of Zoning Adjustment of a proposed 200-foot tower requested by radio station WINX.

Western Union Telegraph Company building location. Sanborn Map Company fire insurance map showing footprint is inset.

Western Union bought the property at 4623 41st Street NW in September 1945. The next month, the Washington Evening Star reported that the company was planning to build a 90-foot tower “for wireless transmission of messages along a chain of towers.”Western Union hired Washington, D.C., architect Leon Chatelain Jr. (1902-1979) to design the new Tenley transmission tower at the site which was at 397 feet above sea level.

The Washington terminal is a communications tower and attached equipment. The facility was constructed on a rectangular block on the east side of 41st Street N.W. immediately north of 41st Street’s intersection with Wisconsin Avenue.

D.C. Surveyor’s Office wall survey plat showing Western Union building.

The tower is an octagonal masonry structure that rises 90 feet above the ground level. It measures measuring 9′-3″ on each side and is attached to the square equipment wing which measures 38 x 40 feet. The tower was built on a concrete foundation (below-grade footer) and is constructed of brick walls and its exterior is clad by dressed limestone facing. There are five internal floors within the tower and an 11-foot-high aluminum turret housing microwave antennas caps the flat roof. The first floor consists of an office space and maintenance work spaces; access to the upper portions of the tower is via a metal staircase in the eastern side of the tower core. Entry to the tower is through a vestibule and door leading from the rear wing.

Western Union Telegraph Company Tenley terminal rendering by Leon Chatelain reproduced in various Western Union publications.

The tower has rectangular metal-frame windows in the north and south facades at the first, second, and third story levels. The “Tower Floor” (upper) level has eight (one for each side) removable rectangular fiberglass and aluminum panels that conceal the enclosed microwave antennas. The tower walls rise to a low parapet around the flat roof and narrow walkway between the parapet and the aluminum turret.

Western Union Telegraph Company. Proposed elevation drawing by Leon Chatelain.

Western Union Telegraph Company Washington terminal. Proposed plan drawing by Leon Chatelain.

The tower’s decoration is minimal, its style informed by the moderne. Slight curves and tapering along the parapet create an entasis effect. The only ornamentation is the “Western Union” corporate name in 13-foot-high bronze letters on the tower’s west façade.

Western Union Telegraph Company bronze sign rendering by Leon Chatelain.

Western Union sign on the Tenley terminal, 2002.

The attached wing, located on the tower’s east side (rear), was built as a two-story reinforced concrete building to house a battery room, engine room, and other parts of the facility’s physical plant on the first floor and communications equipment on the second story. The facility’s main entrance is through a door on the north side of the tower into the wing’s west façade. The rectangular metal door is set in a rectangular projecting bay with fluting and the building’s address — “4623” — in bronze numerals set above the door. The wing’s west façade is symmetrical: the tower rises in the center and is flanked on the on the north by the building entrance and the south by a rectangular metal-frame window.

The tower and wing were modified several times during the facility’s history. Briefly, in 1948, a 43-foot experimental metal antenna was mounted on the turret. In 1962, Western Union constructed a one-story reinforced concrete addition to the wing on which it built a four-legged lattice tower to mount additional microwave antennas. The added tower rises 155 feet above the addition and two microwave reflector horn antennas cap it, along with an observation platform. The 1962 tower was attached to the one-story addition roof by concrete pedestals.

Chatelain began drafting renderings of the new tower as early as October 1945 and his firm was busy drafting plans for the facility by December of that year. In June 1946, Western Union received a building permit from the District of Columbia to “erect one 2-story limestone & brick building & 90 ft. tower.” Construction began in July 1946 when Western Union’s contractor, Jeffress-Dyer, Inc., demolished a one-story stuccoed frame house at the site; the tower was completed on 24 March 1947.

The Tenley site designed by Leon Chatelain Jr. was modified several times during its use by Western Union. In 1948, Chatelain’s engineers designed a temporary 42-foot guyed antenna to be mounted on the tower’s original turret. The building permit was issued in June 1948, however it is unclear if the extension was ever added. In 1963, Chatelain again prepared designs for Western Union to add a third story to the tower’s equipment wing and a four-legged 165-foot lattice tower with microwave horn reflector antennas. The 1963 lattice tower and horns remain on the building.

Chatelain’s tower is the only architect-designed facility in the first generation Western Union system. Chatelain’s modernist tower is an outstanding example of radio transmission architecture and was built in accordance with prevailing industry standards: “Because a radio transmitter is a very modern phenomenon, it seems appropriate that the transmitter building should usually follow a style belonging within that broad range roughly known as ‘contemporary’.”

Western Union Telegraph Company Jennerstown Relay, Westmoreland County, Pennsylvania. Historic American Engineering Record photograph by Jet Lowe.

Western Union continued to operate the facility until its sale in 1990 to Micronet, Inc. In 1997, Boston, Massachusetts-based American Tower Systems (now, American Tower Corporation) acquired Micronet and all of its assets — including the Tenley site and another Western Union facility in the radio relay triangle in Severn, Maryland. The Tenley site currently is used as communications facility, mainly for personal wireless services.

The 1940 kerfuffle over the proposed WINX tower was replayed at the turn of the 21st century when American Tower Corporation began building a 756-foot broadcast tower. Half a decade of litigation ensued because American Tower Corporation had failed to comply with various laws prior to starting construction. Tenleytown, like other communities throughout the nation where telecommunications companies had begun construction on large towers before fulfilling regulatory requirements, had a partly-built lattice tower looming over homes and businesses until the lattice tower was dismantled in 2006.

American Tower Corporation dismantling its partially built broadcast tower in 2006. Photograph by David Rotenstein.

Coming in Part II: The Fort Reno Presidential Emergency Facility


The material in this post was drawn from the National Register of Historic Places inventory form I completed for the Tenley site and from the 2005 Historic American Engineering Record (HAER) report I wrote that documents the Jennerstown Relay site in Westmoreland County, Pennsylvania. The results of my Western Union Telegraph Company microwave sites research was published “Towers for Telegrams: The Western Union Telegraph Company and the Emergence of Microwave Telecommunications Infrastructure,” IA, The Journal of the Society for Industrial Archeology 32, no. 2 (2006): 5-22. Also used in this post is material from the article on the history of telecommunications towers that I wrote for the Scenic America Website. The definitive Internet source for Cold War telecommunications history and trivia is Albert LaFrance’s A Secret Landscape America’s Cold War Infrastructure Website and Coldwarcomms email list on Yahoo.

© 2010 David S. Rotenstein