The basilica of St. Plechelm is a Roman Catholic church dedicated to the 8th-century Irish monk Saint Plechelm, whose festival on 15 July has been on the calendar of the medieval diocese of Utrecht ever since his canonisation in the 10th century.
The oldest parts of the existing building date from the middle and the second half of the 12th century, but the history of the church goes back to the 8th century, when the traveling missionary Plechelmus founded the first church on the site, the Silvesterkerk, initially dedicated to pope Silvester and sometime before 954 rededicated to Plechelmus himself (canonised after the elevation of his relics).
In 954, bishop Balderik of Utrecht founded a chapter in Oldenzaal and expanded and restored the 8th-century church, allowing the relics of Plechelmus used on his canonisation to be transferred to it. The current tower was erected around 1240. The church was enlarged in Gothic style in 1480s.
References:Střekov Castle (Schreckenstein) is perched atop a cliff above the River Elbe, near the city of Ústí nad Labem. It was built in 1316 for John of Luxembourg, the father of the Holy Roman Emperor Charles IV, to guard an important trade route to Germany. After changing hands several times, the castle was acquired by the Lobkowicz family in 1563. Its strategic importance led to occupations by Imperial Habsburg, Saxon, and Swedish forces during the Thirty Years' War, as well as successive sieges by Austrian and Prussian armies during the Seven Years' War.
Although Střekov Castle was heavily damaged during those conflicts and abandoned as a military installation by the end of the 18th century, the 1800s saw many poets and artists visiting the castle, drawn by a new trend of interest in romantic ruins.