WDTN (channel 2) is a television station in Dayton, Ohio, United States, affiliated with NBC. It is owned by Nexstar Media Group, which provides certain services to Springfield, Ohio–licensed WBDT (channel 26), a de facto owned-and-operated station of The CW, under a local marketing agreement (LMA) with Vaughan Media. The two stations share studios on South Dixie Drive in Moraine, Ohio.

WDTN's transmitter facility is located off Frytown Road in an exclave of Jefferson Township surrounded by the southwest Dayton neighborhoods of Germantown Meadow, Highview Hills and Stoney Ridge; through a channel sharing agreement, it shares its digital channel with WBDT, along with unrelated Richmond, Indiana–licensed Ion Television O&O WKOI-TV (channel 43).

The construction permit for what is now WDTN was awarded to the Crosley Broadcasting Corporation of Cincinnati on April 4, 1947. It was the first broadcast television license granted by the Federal Communications Commission (FCC) to Dayton. However, due to several delays, the station did not actually go on the air until March 15, 1949, as WLWD, on channel 5, twenty days after CBS affiliate WHIO-TV began broadcasting. From the very first day, it has operated from a studio and office facility located in a former skating rink on Dixie Drive in Moraine. (The property has changed jurisdictions since the original airdate: first it was within the now-defunct Van Buren Township, which voted to incorporate as Kettering in November 1952; in 1953, the western portion of Kettering, which included the property, voted to secede, forming Moraine Township, which in turn incorporated as Moraine in 1957.)

WLWD was the second link of a group of inter-connected stations which made up the "WLW Television Network", and was named for Crosley's flagship Cincinnati radio station WLW; the "D" referred to Dayton. The other stations were WLWT in Cincinnati and WLWC (now WCMH-TV) in Columbus, both also owned by Crosley. The three outlets shared common regional programming, most of which was produced in Cincinnati and sent by way of microwave link to Dayton and Columbus (such as The 50-50 Club with Ruth Lyons, and later Bob Braun; The Paul Dixon Show; and Midwestern Hayride). All three stations were also NBC affiliates, and had secondary relationships with the DuMont Television Network; WLWD also carried ABC programs. The first program shown on WLWD was NBC's Texaco Star Theater, with Milton Berle. To reflect their connection to each other, the WLW Television stations hyphenated their call signs on air; the Dayton outlet was known as WLW-D. The Crosley television group would later expand to include WLWA (now WXIA-TV) in Atlanta, WLWI (now WTHR) in Indianapolis, and WOAI-TV in San Antonio.

The release of the FCC's Sixth Report and Order in 1952 resulted in shifts of VHF channel assignments in the Midwest region. In Ohio, WLWD's channel 5 allocation was moved to Cincinnati and given to sister station WLWT, with the Dayton station reassigned to transmit over channel 2. WLWD's channel change took place on April 27, 1953. WHIO-TV, Dayton's only other station at the time, also shifted channels (from 13 to 7) as a result of the same ordinance. Along with the channel shift WLWD was also forced to operate with a shorter transmission tower, to reduce the overlap of its new channel 2 signal with the relocated signals of WLWT (which moved from channel 4 to channel 5) and WLWC (which shifted to channel 4 from channel 3). The analog channel 2 signal traveled a very long distance under normal conditions.

WLWD lost DuMont in 1955, a few months before the network shut down. It lost ABC in 1965 (though it cleared some ABC daytime programming until 1971 as a secondary affiliate) when then-independent WONE-TV (channel 22, now WKEF) picked up ABC's prime time programming.

In 1968 the Crosley group took on the name of its parent company and became known as Avco Broadcasting, a subsidiary of the Aviation Corporation (later known as Avco). After the FCC restricted the common ownership of stations with overlapping signals in the late 1960s, it grandfathered Avco's common ownership of WLWD, WLWT, WLWC and of WLW radio in Cincinnati. Even from its shorter tower, WLWD's city-grade signal reached as far as Cincinnati and as far north as the Columbus suburbs, while WLW radio's 50-kilowatt signal covered nearly all of Ohio and overlapped with all three television stations.

In 1975, Avco decided to exit broadcasting. As a result, WLWD lost its grandfathered protection, and had to be sold off separately from WLWT and WLWC. WLWD ended up being the last of Avco's television stations to be sold off, going to Grinnell College in Iowa for $13 million in June 1975; the acquisition made Grinnell College one of a few universities in the country to own a commercial television station. The school changed the call letters to WDTN shortly after the sale closed on June 16, 1976. Not long after Grinnell took over, WDTN increased the height on its broadcast tower and began operating at full effective radiated power, increasing its coverage area. (The WLWD call sign was used from April 2003 until April 2010 for an FM radio station serving Lima, now WBKS. The call sign has been used since October 12, 2010, by Daystar station WLWD-LD (channel 20), licensed to Springfield.)