Roskilde Cathedral, Denmark
Roskilde Cathedral is a Protestant Cathedral located on the ridge at the very heart of Roskilde fjord, the Island of Zealand, Denmark. According to the historian Adam of Bremen the first church was from wood built about 980 and was replaced by stone church about 1080. Present Brick Gothic cathedral was built during the 12th and 13th centuries.
Riga Cathedral, Riga, Latvia

Riga Cathedral is famous for its organs constructed between 1882 and 1884 by German company E.F.Walcker & Sons with 6718 pipes. The organs were at that time the largest and the most modern in Europe. Besides organ concerts and festivals Riga Cathedral also houses a museum which displays pictures of Riga between World War I and World War II including the maps and postcards of Old Riga.
Oude Kerk, Amsterdam, Netherlands
Oude Kerk (Old Church) is a Protestant church located alongside a canal in the Red Light District in Amsterdam, the Netherlands. Oude Kerk is the oldest church in Amsterdam. It was consecrated by Guy of Avennes, bishop of Utrecht in 1306 although the construction works probably began about 1250. The church went through numerous alterations over the next centuries. The present Gothic style dates from the 14th century, while Gothic-Renaissance spire was built in 1565. Oude Kerk was confiscated by the Protestant reformers 1578 when Amsterdam officially became a Protestant city and much of its Catholic decoration has been destroyed.