Korniakt Tower, Renaissance bell tower on Pidvalna Street, Lviv, Ukraine.

Korniakt Tower is a square stone bell tower attached to the north facade of the Dormition Church on Pidvalna Street, not on Market Square. Built of rubble stone faced with cut stone, it rises 65.8 meters without the cross. Its tiers decrease in height, and the facades are decorated with Tuscan pilasters and red arched niches.

Built in 1572–1578 as the bell tower of the Dormition Church, designed by architect Petro Barbon with Pavlo Rymlianin, paid for by the Greek-born Lviv merchant Kostiantyn Korniakt. It replaced an earlier tower funded by David Rusyn, which collapsed in 1570. After a fire during the Turkish siege of 1672, Petro Beber rebuilt it in 1695, adding a tier and the baroque top with four twisted obelisks.

The tower served as the emblem of the Dormition Brotherhood, appearing on its seals and publishing marks. During religious feasts a chapel band played and the brotherhood choir sang on the gallery of the upper tier. The brotherhood also used the tower as a place of punishment for members who broke its rules; Yurii Rohatynets was confined there once.

The tower stands at Pidvalna Street 9, joined to the north facade of the Dormition Church, a short walk from Rynok Square. It is part of the Lviv Historical Museum, so entry follows the museum's arrangements rather than a separate tower ticket. The bell gallery of the upper tier, where the brotherhood choir once sang on feast days, is not described in the sources as open to climbers.

The tower served as a defensive post during sieges and as a lookout for the fire watch. Its bell "Kyrylo", cast to Korniakt's order, was about 2 metres across and became Lviv's main bell, announcing fires, military danger and the deaths of leading citizens regardless of their faith.