St. Marien Church Flensburg

The Catholic Church of St. Mary's Sorrowful Mother in Flensburg was built between 1898 and 1900 in the neo-Gothic style according to plans by the architect Heinrich Flügel. The Roman Catholic parish church is one of the cultural monuments in Flensburg's city center.de.wikipedia.org/wiki/St._Marien_Schmerzhafte_Mutter#cite_note-A-1

The lead-glazed windows are sensational

The Evangelical Lutheran St. Marien Church is one of the two largest and most important churches in Flensburg. Its history is closely linked to that of the city. It rises above an old settlement center on the gently rising western bank above the Flensburg Fjord north of the Nordermarkt.
The parish of St. Marien was probably built after the Danish King Knud VI came to power. begun in 1182. The victory over the Wendish pirates made Baltic trade possible and led to the construction of ships with a greater draft, which, however, could no longer call at the shipping settlement of St. Johannis, located at the end of the fjord at the time. It was probably merchants from the Knudsguild, originally based in Schleswig, who founded the new market town with a ship dock. The layout of the parish of St. Marien followed the pattern of the German founding town: a square market square (the Nordermarkt), with streets running at right angles to the corners and a "row of stalls" from the market church(st-marien-flensburg.de/mehr-zur-kirche)