Castell ( ) is a small unincorporated, rural town in Llano County, Texas, United States. It is part of the Texas German belt region, and most residents are still ethnic German-Texan. Its population was 104 at the 2010 census. Located in the heart of the Texas Hill Country, its northern border is formed by the Llano River. It was designated a Recorded Texas Historic Landmark in 1964, marker number 9440. Founding Castell began in 1847 as a land grant in Comanche territory settled by German abolitionists and Free-Soilers. The unsettled land had formerly been part of the Fisher–Miller Land Grant. It was part of a series of immigrant settlements sponsored by a group of prominent Germans known as the Adelsverein, including Count Emil von Kriewitz, John O. Meusebach, Prince Carl of Solms-Braunfels, Hermann Spiess, Gustav Schleicher, Ferdinand Ludwig Herff, and Count Carl Frederick Christion of Castell-Castell (1801–1850). Count Castell was the vice president and business manager from the beginning of the Adelsverein until about the time of Castel's founding. The other communities were Schoenburg, Meerholz, Leiningen, and Bettina. The first two were unsuccessful from the start. Leiningen and Bettina had brief lives, with Bettina lasting only a year. Only Castell remains in Llano County. Describing conditions in Castell in the mid-19th century, a tour guide has written Mormonism Castell briefly experienced an influx of about 20 Mormon pioneer families under the leadership of Lyman Wight. They had settled in Zodiac, Texas, in 1847, in Mormon Mill in 1851, and then settled in Castell briefly before moving south in 1854 to Bandera, Texas. Wight died on March 31, 1858, and his body was returned to Zodiac for burial. Due to the Mormon custom of sending out missionaries, the Castellite congregations of 19th-century North Carolina possibly took their name from the Mormons who lived briefly in Castell, Texas. Modern era The community was originally on the north bank of the Llano River, but now is on the south bank in the western part of Llano County near the Mason County line. Castell had a population of 72 people in 1972 and again in 2000. In 2007, a Castell promotional site claimed a population of only 23. Castell is in the Central Time Zone and is assigned ZIP code 76831 and area code 325. Castell has several small businesses, mainly centering on camping and hospitality as a result of the flyfishing and kayaking