Kosterin House, Ufa, Regional heritage building at Karl Marx Street, Ufa, Russia.

Kosterin House is a three-storey stone mansion at the corner of Pushkina and Karl Marx Streets in Ufa, built for merchant Pavel Kosterin. Its two front façades form a U-shaped plan with two entrances; the main entrance and main façade face Karl Marx Street. An elliptical attic window marks the corner, and the façades carry Art Nouveau stucco ornament, balcony railings and bas-reliefs. Inside, the ground floor has enfilade halls with moulded ceilings, oak doors 3 m high and cast-iron staircases by Gutman.

Pavel Kosterin, a merchant who arrived in Ufa from Samara around 1890, bought two estates at the corner of Pushkinskaya and Aleksandrovskaya (now Karl Marx) streets, demolished the old wooden houses and built this three-storey stone mansion for about 30,000 rubles. Sources date its completion to either 1907 or 1912, and its architect is attributed to Konstantin Guskov or A. A. Shcherbachyov. In spring 1919 it served as Admiral Kolchak's military headquarters; from June 1919 it housed the political department of the 25th Rifle Division under Vasily Chapayev.

The façade carries a stucco image of Kosterin's wife, Yekaterina Pavlovna, née Popova, daughter of a wealthy merchant. A legend held that before 1917 the mansion also served as a brothel. Since 1997 the building has housed the Bashkortostan customs office.

The building currently operates as a working federal customs office, so interior access is limited, but you can view its exterior and architectural details from the street. Walking around the structure allows you to appreciate the symmetrical facade and ornamental stonework from different angles.

This residence was among the first private homes in Ufa to feature central heating, powered by an innovative boiler system installed in the basement. This modern comfort feature was groundbreaking for residential buildings in the region at that time.