Sanatorium and Spring House for Dr. Kristóf Fogolyán, Kászonjakabfalva

Near Kászonjakabfalva, on the gently rising, pine-covered slope of an isolated valley, this two-storey stone-and-timber house was built over a mineral-water spring and carefully composed into the surrounding landscape. The water of the Balás Spring at Borárnyék had been commercially exploited already before the turn of the century and circulated under several names. The bottling plant and spa of the Veresszéki Spring—later known as the Pán, and subsequently the St. George Spring—operated between 1894 and 1956.

Károly Kós’s client was the new lessee of the mineral-water site, the Sepsiszentgyörgy physician Kristóf Fogolyán, who marketed the water under the name “Pán.” For his close friend, Kós also personally designed the advertising graphics, labels, and promotional posters.

An earlier sketch design from 1918 indicates that Kós had already begun working on the project at that time; however, the design corresponding to the realized building is understood to have been prepared between 1924 and 1926.

The architect positioned the spring house directly on the slope, so that the massive stone base appears as a rocky escarpment among the pine trees. This placement also served practical purposes: bottled spring water could be transported from the cellar level directly to carts waiting in the clearing in front of the building, while the upper residential level was accessible directly from the rising terrain behind. Instead of shingles, the roof was covered with locally produced tiles from Bacon.

The building was later extended. In the 2000s, a full reconstruction was initiated after the structure—used for a long period as a cowshed—had fallen into a severely dilapidated state. The reconstruction was carried out under the direction of architect Győző Esztány and was completed in 2022.