Balneotherapy — therapeutic bathing in hot springs — has been attracting visitors to Piestany, Slovakia since the 17th century. Today, a treatment area and five hotels are situated on Spa Island in the River Váh, the source of the healing thermal waters and sulfuric mud.

Many guests eschew the four modern hotels built in the 1970s in favor of the "Thermia," the oldest accommodation here, with its accompanying treatment hall named "Irma," both built in 1912. Thermia and Irma stand as superb examples of eclectic and late art nouveau styles.

In 2003, conservation procedures were undertaken by a team supervised by architect Stanislav Chorvat. Particularly notable was work conducted on the structure surrounding the unique, round 5400-square-foot (500-square-meter) mud pool.

"The pool had been built above the hot springs and mud deposits, on wooden piers with a reinforced concrete column base that continues to the cupola top in the form of ribs," explains engineer Imrich Reichel, a member of the team. "The pool was in a deplorable state due to the aggressive sulfur vapors and the insufficient airing." The cupola and the concrete construction were corroded, the masonry was wet, and plaster work was peeling off.

The reconstruction involved the reinforcement of the structural elements, treatment of existing surfaces and walls, restoration of glazing to match the original drawings, and artisan work on the ceramic tile.

Because Irma is a protected cultural building, the team's goal, to return the building to its original architectural composition, was not easy. Supplies had to be delivered through a hole of roughly 11 square feet (one square meter). And because the whole subfloor is mud, and not capable of supporting scaffolding, workers had to lay out steel beams, supported at the pier positions, and erect the scaffolding on the beams. The entire cupola construction was pieced back together over the pool.