It was not until the 18th century that the settlement of Kahlert was established at the junction with the Rennsteig, the first mention of which dates back to 1727. At this time, the Rennsteig was the border between the Schwarzburg and Ernestine territories, from which Schwarzburg-Rudolstadt and Saxe-Meiningen ultimately emerged. As the Rennsteig runs east past the houses of Kahlert, the settlement belonged to the Saxe-Meiningen part of the divided town of Neustadt am Rennsteig. After the state of Thuringia was founded in 1920, a municipal reform was carried out in which both halves of Neustadt, together with Kahlert, formed a municipality in the new district of Arnstadt, from which today's Ilm district emerged.

Today, the small settlement of Kahlert belongs to Neustadt am Rennsteig, which in turn is part of the rural municipality of Großbreitenbach.