The Church of St. Nicholas the Wonderworker is a Russian Orthodox church built between 1825 and 1827 on an old Russian church according to the plans drawn up in 1807 by the architect Luigi Rusca. The neoclassical church is one of the first domed churches in the capital.
St. Peter and Paul's Cathedral was designed by Carlo Rossi and completed in 1841. It is the Catholic Cathedral of Tallinn. During the period of Swedish rule (1561-1721) Catholicism was banned. When Sweden ceded Estonia to the Russian Empire at the end of the Great Northern War, the new authorities introduced religious freedom. In 1799, the Catholic parish grew and took over the use of the former refectory of St. Catherine's Monastery, which had remained closed since the ban. The refectory was used as a place of worship and is located on the site of the present church. In 1841, as the place of worship had become too small, a new church was designed by Carlo Rossi.
St. Olaf's Church was founded in the 12th century by the Scandinavians who occupied the city at that time and was named after King Olaf II of Norway. The building has been preserved as it was rebuilt in the early 15th and 16th centuries. The church also had to be partially rebuilt after fires in 1625 and 1820. The tower, which was destroyed in the fire of 1820, was restored in 1840, and at the same time, the neo-gothic interior of the church was completed.