Here is a comprehensive summary of the Wikipedia article on WTHR:

WTHR (channel 13) is an NBC-affiliated television station in Indianapolis, Indiana, currently owned by Tegna (a subsidiary of Nexstar Media Group) alongside WALV-CD, with studios in downtown Indianapolis and a transmitter in Carmel. It first signed on the air on October 30, 1957, as WLWI, an ABC affiliate founded by the Crosley Broadcasting Corporation, and was part of the regional WLW Television Network that shared programming with sister stations in Ohio. The station was embroiled in a heated licensing dispute from 1957 to 1962, which was resolved when Crosley traded its Atlanta station (WLWA) to competitor Richard Fairbanks to retain the channel 13 license. In its early years, WLWI struggled in the ratings, often finishing third or even fourth behind rivals WFBM-TV and WISH-TV, partly due to ABC's weaker network standing at the time. After Crosley was renamed Avco Broadcasting, the company announced in late 1974 that it was exiting the broadcasting business, leading to a change in ownership and the station's eventual rebranding as WTHR. Today, WTHR serves as a major NBC affiliate in the Indianapolis market, having overcome its early struggles to become a prominent local news outlet.