Now a neglected outpost near Krakow, the village of Wiślica was once a thriving religious and political center of medieval Poland. A church built by members of the ruling Piast dynasty in the second half of the twelfth century featured a magnificently decorated gypsum floor preserved by the later Romanesque and Gothic churches built atop it. In 1959–1960, excavators rediscovered the gypsum flooring three meters below the current 650-year-old church (Collegiate Basilica of the Birth of the Blessed Virgin Mary), marveling at its portrait of Piast dukes—the earliest-known—surrounded by a Latin inscription and rich floral and zoomorphic designs. An underground exhibition hall was built to display it in situ in 1963. The gypsum flooring and its surrounding archaeological context were the subject of painstaking conservation efforts in the mid-1980s, but the lack of maintenance of the present Gothic church led to considerable water and salt damage. The exhibition hall was closed in 1987. Damage to the flooring by vandals in 1998 had led to soiling and subsequent microorganism infestation. Support from the General Conservator of Monuments in Poland allowed an emergency intervention that conserved of the archaeological remains, but the lack of a comprehensive plan for restoration and maintenance continued to threaten the site.
2002 World Monuments Watch
After inclusion on the 2002 World Monuments Watch, WMF secured support from the Samuel H. Kress Foundation for the creation and implementation of a comprehensive plan to remove the most pressing threats to the site and return public access to the crypt. A one-year microclimate measurement campaign, documentation of existing conditions, and the analysis of archival material relating to the deterioration and conservation of the site over 40 years revealed inadequate room climate. The main cause of deterioration was groundwater infiltration through the foundations, exacerbated by a faulty drainage system installed in 1963 on the wall adjoining to the gypsum flooring. Following an investigation of the hydrogeology of the entire site, the team cleaned and repaired the existing drainage system and waterproofing constructions, replacing damaged sections with new materials for better protection against water permeation. The yearlong project was completed in December of 2003, and the site was opened to the public.
The protective measures undertaken with support from WMF allowed for the reopening of the site to the public. After being closed for sixteen years, local and international visitors are now able to see this medieval treasure.