The Preservation Project of St. Wenceslas Rotunda at the Lesser Town Square in Prague

Current Condition of the Monument and Its Preservation Project

The years of 2004 and 2005 saw the first part of an archaeological survey and urgent preservation actions: reinforcement, treatment of uncovered historical constructions, and construction works necessary for the preservation of the historical site. Basic climactic conditions were secured. Both the monument’s current state and its cultural significance, however, require its speedy conservation and restoration, in order to forestall its continuous degradation and the risk of destruction. Authorities concerned have recommended the future course of these works, according to which a project of preservation, necessary adjustments, and of conservation methods was designed. A great number of experts and scientists from a range of disciplines were involved in the preparation of the project. The aim of the project is not only to preserve this significant monument, but also to render it accessible to the public.

Aims of the Project

The project is aimed at protecting and preserving the cultural monument of St. Wenceslas Rotunda as an integral structural component of the former Jesuit Professed House, an immovable cultural monument registered in the Central List of Cultural Monuments under reg. no. 38926/491-03, located in the conservation area of Prague, which was declared UNESCO World Heritage Site in 1993 and is protected by law and Government Act no. 66/1971 Coll. on the conservation area in the capital of Prague.

Another aim of the project is to make the public acquainted with the exceptionally valuable historical, architectural, and archaeological findings (fragments of Romanesque masonry, original Romanesque ceramic tiling, and the remains of a circular object from the 10th/11th century). Although lost and forgotten for many centuries, the rotunda is a very unique monument of Czech history endowed with great value. Therefore, the ultimate goal of this project is to allow public access to this site and to present the monument as a constituent part of Czech cultural and historical heritage.

The project is a part of the EAA and Norwegian Grants - CZ06 (Protection and Preservation of Cultural and Natural Monuments and Rendering Them Accessible to the Public). A total of 209 grant proposals were submitted, 26 of which received the recommendation of the Evaluation Committee and were subsequently approved by the Ministry of Finance of the Czech Republic. Details of the first call/draft can be found here.

The Project Team

The project team will be composed of Charles University employees as well as external experts. Necessary for its success is the highest level of cooperation during the restoration, archaeological, and construction works, which shall complement, and follow after, each other in the course of the project. The total estimated period of these works is 16 months, with the individual actions designed so as to ensure their most effective execution.

The project will provide a platform for interdisciplinary cooperation of experts, as well as for an increase in the qualification of university students (especially in the fields of restoration and archaeology). Students will have the opportunity to gain professional experience through university-based practice and the production of student research papers. The restoration of the monument will require the use of traditional materials and technologies, as well as innovative methods. Therefore, the students’ involvement in the project will not only correspond to the concepts and strategies of the individual subjects, but will also allow them to acquire valuable practical skills in preserving and restoring cultural heritage as well as rendering it publicly accessible.

Restoration Works

The historical value of the actual excavation site is so momentous that all the works conducted here are either directly of the restorative nature, or must be conducted under the direct supervision of restorers.

Individual restoration works will be conducted throughout the duration of the project:

  1. Restoration of Romanesque masonry,
  2. Restoration of Romanesque tiling - inspection and stabilisation,
  3. Conservation of archaeological findings from the southern part of the nave,
  4. Manufacture and installation of replicated tiling,
  5. Placement of historical stones - their display,
  6. Adjustment of the other walls,
  7. Murals - colour retouching,
  8. Mounting of photo-profile on the wall,
  9. Documentation of the restoration - a report.

Related works conducted either directly by restorers or by craftsmen under expert supervision will include the following: security, demolition, and supplementary works, minor masonry and stonework, painting, fire adjustments.

Construction Works

The construction part of the project ensuring the accessibility of the rotunda and the adaptation of the space for presentation purposes will include:

  1. Adjustment and finishing of the entrance space, construction of stairs connecting the entrance to the pedestrian bridge, installation of metal pedestrian bridge
  2. Finishing of the traverse wall,
  3. Wiring and lighting,
  4. Installation of special air-conditioning equipment (air-conditioning and ventilation unit including the “MaR” control unit).

The entrance to the rotunda will be formed by the installation of a stone slab on the level of sandstone stairs leading to the hall, which will be connected to the steel construction of the pedestrian bridge by its four stone-clad steps. Both the stone masonry constituting the crypt and the Baroque masonry will be cleaned, and the inlets and passages of the engineering system will be covered up on both sides of the entrance. The entire rotunda will be bridged by a steel pedestrian bridge (1040mm wide and 9515mm long), which will be anchored in two concrete base constructions built specially for this purpose. Newly constructed brickwork will be placed in the centre of the rotunda’s circular ground plan as support for the steel bridge, and in order to reinforce the upper level of the clay flooring of the rotunda. The eastern wall will be covered by new, plastered brickwork. The northern wall will be completely cleaned, plastered, and painted once the colour has been agreed on.

The lighting in the rotunda is conceived as indirect. All lights will be installed inside the bridge or underneath it. Spotlights will illuminate the floor surface of the bridge. The entire floor area of the space will be illuminated by line lights which will be installed under the supporting structure of the bridge. Other line lights will illuminate the entrance to the rotunda around the sandstone masonry. The northern part of the rotunda will be illuminated by spotlights and halogen lights.

The installation of a special air-conditioning unit is an essential part of the construction works. Its role is to ensure microclimatic conditions for the purpose of protection and preservation of the historical features and artefacts of the rotunda.

Archaeological Works

Archaeological works are divided into five phases that will take place throughout the duration of the project.

  1. Continuation of the field research initiated in 2004-2005
    1. Supervision of the construction and restoration works in progress, supervision of the uncovering of layers
    2. Documentation of archaeological and physical findings
    3. Sampling of exposed layers
  2. Processing of the findings of the field research from the years 2004, 2005, and 2014 - the result will be a professional reconstruction of the historical development of the rotunda and of the site on which it was built. It will also be classified in terms of temporal relations by means of physical findings.
    1. Production of graphic output,
    2. Production of charted output,
    3. Production of flow chart for the site,
    4. Processing of findings - classification of findings for drawings, conservation, descriptions, and evaluation.
  3. Analyses
    1. Analysis of 30 samples of mortar extracted from masonry and floor bedding,
    2. Geochemical analyses of samples of slag, ore, metal, unusual coated smear, pigment, spindle whorls, melting pots, indeterminate and questionable findings,
    3. Radiocarbon analysis 14C,
    4. Palynological analyses of stored samples of clay with microbotanical remains,
    5. Geochemical analysis of historical terrain samples, among them types of clay and ash,
    6. Geological report.
  4. Historical Evaluation of the Archaeological Research
    1. Reconstruction of the historical development of the site,
    2. Comparison of acquired knowledge with legends and written reports,
    3. Reconstruction of the architectonic development of the object and its comparison with analogous buildings,
    4. Analysis of found movables,
    5. Historical contextualisation of substantial and non-substantial findings.
  5. Output Production - graphic, tabular, and textual