About St. Isaac's Cathedral
The enormous columns prepare you for an interior that also works on a grand scale. In Auguste de Montferrand's design, look at the painting, sculpture and mosaics; at the iconostasis, malachite and lapis lazuli set green and blue among the gold.
Visiting the interior and climbing the colonnade are separate activities. Choose according to your interests and your appetite for stairs; the view is no substitute for the works inside, and the museum ticket doesn't automatically include the viewing deck.
