Sioux City (Iowa) had its own Lithuanian St. Casimir church (2524 Leech Ave) among its early 20th century imigrant heritage when the Missouri River served as America's main highway and the cities on its banks swelled from factory workers.
Sioux City St. Casimir church had enough architectural value to be inscribed into the National Register of Historic Places on 1998. Originally funded by 1000 local Lithuanians (in 1915) in a place near city stockyards the church was designed by a famous Prairie School architect William L. Steele who decided to build the iconic domed tower on an otherwise simplified gothic revival building. William L. Steele was also responsible for the Woodbury County Courthouse building.
The church interior has also been impressive, created by a Lithuanian-American Adolfas Valeška ~1950. Like many new members of the congregation at the time he was a Lithuanian artist on the run from Soviet genocide and censorship. He is also known for having created props for Chicago Lithuanian opera.
Sadly, the NRHP inscription did not save the church from the diocese-induced demise. Wishing to do away with the ethnic parish the Diocese of Sioux City forbade accepting new members ~1990 (even though the parish was solvent), held the final mass on 1998 and torn down the historic church building on 2007. Only the old priest's house remains on the site while the church itself has been replaced by a modern single-floored detached dwelling. The Valeška's interior decorations and even the dome have been saved however through the ardous work of the local Lithuanians.
Sioux City was the second westernmost city in the world to have a Lithuanian church (after Los Angeles).