Peter's first concern in the creation of St. Petersburg was with the defense of the approaches of the Neva river delta, and the Peter and Paul Fortress was the first major building project undertaken. In fact, it is entirely possible that the idea of building a new capital city on the site occurred to the young Tsar while he was living in his cottage and supervising the fortress's construction.
The primary attraction within the fortress is the Peter and Paul Cathedral, begun by Peter as soon as the fortress had been constructed, though not completed until 1733. In keeping with Peter's Eurocentric bias, its design follows the pattern of Dutch ecclesiatical architecture rather than Russian. The most noticeable characteristic of this is the cathedral's tall thin spire, which was designed specifically so as to best Moscow's Ivan the Gret Belltower as the tallest structure in Russia. The cathedral is the resting place of most of the Romanov monarchs (excepting Peter II, Ivan VI, and Nicholas II), and their sarcophagi can be viewed inside.

Address:
3 Petropavlovskaya Krepost
Open: 11.00 - 17.00
Closed on WED and on the
last TUE of every month.