Right by the Royal Palace, stands the Storkyrkan, or Stockholm Cathedral. Parts of the building date from the 13th century, and as a result it's a mixture of Gothic, Romanesque and Baroque styles. Pop inside and check out the octagonal vaulted domes and the impressive silver altar. This is where crown Princess Victoria married Prince Daniel in 2010.
Address: Trangsund 1, Stockholm
Phone: 46 8 723 30 00