Platy limestone
as cultural heritage

Carso (Appendices 3.I.1 and 3.II.1)

Stone is a typical building material for Carso/Kras, which was already in use back in prehistory, largely for the filling of ramparts of hill fortresses. The first reports of stone roofing, which became popular due to its availability and resistance to harsh weather conditions (e.g. the bora wind) date back to the Middle Ages.

Quarries were in use already in Roman times, but the majority were only exploited during and after construction of the Vienna-Trieste railway and which are, however, quarries of homogenous limestone; platy limestone was collected in smaller local delves.

Typical uses of platy limestone over the entire Carso/Kras territory are dry walls that were used to demarcate fields, properties and similar, but were also simply deposits of stone material during the clearing of fields. Small stone shelters with roofs made using a corbeling technique are usually connected with the walls. Platy limestone is used mainly as a roof covering on private houses and on churches. Typically houses are small, single-cell houses, sometimes with an additional, often detached kitchen (spahnjenca); or somewhat larger structures with a second floor and an external staircase, that usually represent living part of a domestic homestead with a walled farmyard. Churches are usually single-nave buildings with an attached presbytery and a bell-gable or bell tower above the entrance.

A total of 148 buildings from Carso were documented

A total of 148 buildings from Carsowere documented: 23 from Aurisina, 11 from Basovizza, 3 from Borgo Grotta, 3 from Bristie, 4 from Ceroglie, 5 from Zolla, 3 from Colludrozza, 7 from Gabrovizza, 2 from Malchina, 7 from Precenico, 2 from Prepotto, 23 from Rupingrande, 3 from Rocca of Monrupino (Fig. 3.5), 11 from Rupinpiccolo, 5 from Sales, 1 from Samartoza, 1 from San Giovanni, 1 from San Lorenzo, 4 from San Pelagio, 14 from Santa Croce, 5 from Sgonico, 6 from Silvia, and 4 from Trebiciano.

The selected examples from the Italian region well represent the above-mentioned typology. Rupingrande/Repen buildings are typical homesteads with walled farmyards, probably from the 18^th century. They have been renovated and are in public use as museum houses. The Ljenčkica house and a community house from Col are small, single-cell objects that may be even older. A fifth example is a small community house from Santa Croce/Križ, built in the 17 ^th century (1646) as a refuge to escape the plague (see Annex 3.I.1.1).

Due to a lack of construction companies able to restore roofs in the traditional way, most every stone roof has simply been pulled down in the past 10 years and rebuilt with a structural concrete roofing supporting the stone slates. The concrete roofing rests on a concrete beam constructed atop parametrical walls.

Only a few roofs retain their original structures, which is largely the result of the owners maintaining them by replacing broken slates and putting lime between them.

The Community of San Dorligo della Valle/Dolina (Appendix 3.I.2)

In the community of San Dorligo della Valle/Dolina on the western edge of the project area specific morphologic stone sections are linked to surprisingly vast variety of solutions in using the local sandstone in traditional, mostly rural architecture. The research in the community of San Dorligo della Valle/Dolina, best described as the area “in transition”, discovered mostly houses and other structures built in local sandstone, with an interesting mixture of Karst and Istrian typology (Fig. 3.6). Three most interesting monuments of cultural heritage have been documented in detail: house in Caresana/Mačkolje, watermill in Bottazzo/Botač, ice pits (ledenice) between Pese/Pesek and Draga Sant'Elia/Draga (see Annex 3.I.2.1).

Kras (Appendices 3.I.3 and 3.II.2)

From the geological and historical point of view, Kras represents a single regional unit, so architectural types and elements on the Slovene side are basically the same as on the Italian side (see above).

In the 19^th century the stone roof was the most usual type of house covering in Kras/Carso. The situation changed drastically with the renovation and modernization of houses during the second half of the 20^th century, when affordable alternative roofing materials replaced stone slates. Stone roofs survived mainly on smaller objects like barns and stables or on abandoned objects, but the lack of maintenance has proved fatal in many cases. Only in recent decades has stone once again become respected, but now new problems arise: a shortage of appropriate materials and skilled craftsmen on the one hand, and new, demanding technical standards on the other.

From Slovenian Kras/Carso 45 buildings were documented: 2 from Gorenje pri Divači, 3 from Povir, 1 from Merče, 3 from Šmarje pri Sežani (Fig. 3.7), 3 from Križ pri Sežani, 4 from Štanjel, 1 from Lokev, 2 from Žirje, 1 from Tomaj, 2 from Dutovlje, 2 from Skopo, 3 from Kopriva, 1 from Tupelče, 1 from Volčji grad, 4 from Divača, 1 from Škocjan, 3 from Vrhovlje, 2 from Voglje, 4 from Kazlje, 1 from Filipčje Brdo, 1 from Plešivica pri Povirju (“Gura pri Povirju”) (Fig. 3.8).

Slovene showcase examples reflect types and situations prevalent in the region: Škrateljnova house at Divača and the “Pri Blaževih” homestead at Gorenje represent good examples of single-floor houses within a farmstead with well preserved details. Two churches are from the 16^th century and one from the 19^th, with typical bell gables or bell towers. The older church has steeper roofs than the younger one (see Annex 3.I.3.1).

Istria (Appendix 3.I.4)

In the Croatian part of the Istrian peninsula, too, limestone quarries were concentrated in the coastal region throughout antiquity, owing to the possibility of transport and the proximity of towns where building materials were needed.

Many stone shelters and omnipresent dry walls are still well preserved. In the rural parts of Istria stone roofing can still be found relatively often, but maintenance remains in the hands of owners, since only a small number of objects is protected. A typical Istrian house is built entirely from stone, with many elements fashioned from platy limestone, particularly roof coverings, but also chimneys, dovecots (Fig. 3.9), pavements, balconies, shelves, stairs and kennels.

Several rural churches are preserved. These are small and modest, simple-shaped, single-nave buildings, frescoed on the inside, with gable roofs and generally a single (sometimes semi-circular) apse, sometimes inscribed on the external side. According to their state of preservation and location along the Istrian peninsula, we can assume that most of them originally had a roof as well as other architectural elements made of stone slabs. Some 39 churches with elements or roofs of platy limestone have been identified, most of them protected as cultural heritage.

No studies that analyse houses and other building typologies present in Istria exist. This gap must be filled in order to preserve the traditional architecture in its physical reality, with specific studies on construction materials and techniques and their availability and viability today, all of which has been largely neglected by most of the scientific communities.

In Istria 22 buildings were documented: 1 from Bačva, 5 from Bale, 1 from Barban, 1 from Draguć, 1 from Fažana, 2 from Kanfanar, 2 from Mednjan, 1 from Sv. Petar u šumi, 1 from Škitača, 1 from Višnjan, 5 from Vodnjan, 1 from Beram (see Annex 3.I.4.1).

Northern Dalmatia (Appendices 3.I.5 and 3.II.3)

Because of its availability, workability and price, platy limestone long served as the main construction material throughout Dalmatia, from prehistory to the appearance of reinforced concrete in the 19th century. Since it was the only widely available building material it would seem destined to be an integral part of the traditional architecture of the region. However, historical documents on this stone are rare. It was not useful for fine stone carving, nor for processing, and was not valued as an architectural stone. In fact, it was considered a most ordinary construction material, much like sand, water or lime. Basically, this stone was excavated on the surface in nearby settlements, and very rarely in quarries. Plate stone has now lost its original role in construction and has only a decorative role today. The original use of the plate remains, however, in the practice of stone conservation.

In Roman times limestone was extracted from quarries on nearby islands (Fig. 3.10). The largest of these were located on the islands of Lavdara, Sestrunj, Dugi otok, Kornati, Žut, Rava, etc. With the fall of the Roman Empire stone exploitation in the Zadar area virtually stops. In the late Middle Ages antique quarries on the islands around Zadar re-open and some new ones start working as well (the quarries Zapuntel, Kamenjak and Zagračina on the island of Molat). After World War I, quarrying is still largely concentrated on the islands and falls further into decline. With the 1960s quarrying comes to a complete halt. So today, for the first time in recorded history, there is no active quarrying in the islands off Zadar.

Modern exploitation techniques with good road transport and connections made the quarries competitive in the hinterland once again. As a result, stone from the Benkovac area became, from the second half of the 20^th century on, a symbol of platy limestone for the entire region of Croatia.

Numerous pre-Romanesque churches were built using crushed stone mixed with plenty of lime mortar. The roofs of these churches were usually covered with stone slabs, and are thus considered the oldest buildings with stone roofing in the area.

The common architecture of the Zadar hinterland and islands has not changed significantly for centuries. Therefore, it is very difficult to determine the age of particular structures. Basically, the most common is a house with a single-cell space covered with a gabled roof, which was covered with overlapping stone slabs (two-thirds overlap). The slabs are massive, with a surface area sometimes exceeding 1 m². In Bukovica and Ravni Kotari, the stones were largely laid in diagonal rows, which was the result of using of relatively large yet thin stone slabs.

Roof maintenance was a simple affair: damaged stone slabs were replaced with new ones. The timbers were rarely changed, usually once over a single generation. On the outside kitchen, slabs were free of mortar. For residential buildings, slabs were largely coated with lime mortar, and the entire roof surface coated with a lime wash. This whitewashing protects the stone, and helps keep clean surfaces on which rainwater collects, with the rainwater directed away to fill cisterns below.

From Northern Dalmatia, 16 buildings were documented: 1 from Benkovac, 2 from Zadar, 1 from Vrgada, 1 from Posedarje, 1 from Parčić, 1 from Medviđa, 1 from Rovanjska, 2 from Nin (Fig. 3.11), 1 from Iž, 1 from Pridraga, 1 from Povljana, 1 from Savar and 1 from Kolarina, 1 from Duće.

Representative monuments were chosen to represent different types of architectures from all three geographical regions and one historical micro-region in Zadar county (town, hinterland, coastland). Even the streets and squares of Zadar were covered with stone slabs, from ancient Roman times through the Middle Ages and up until today. Most of today’s pavements date back to the time of the Austro-Hungarian Empire (late 19^th century).

A typical example of the traditional architecture of Dalmatian Zagora, type Bukovica, is the complex homestead “Čerina dvori” (see Annex 3.I.5.1).

The lack of concern for "minor" rural architecture, as well as the failure to recognize the value of utility infrastructure as part of culture heritage, constitutes the main obstacle in protecting monuments with platy limestone. The sacral monuments of the Zadar region are better protected and enjoy adequate conservation and restoration maintenance work.

Central Dalmatia (Appendix 3.I.6)

The use of stone in architecture is omnipresent in central Dalmatia. It is particularly well preserved on the islands of Brač, Šolta and Hvar. The quarries of Slatina, Plate, Oklade, Zastražišće and Rasohe between Pučišća and Škrip on the island of Brač were working throughout the whole of Antiquity, as traces and reliefs dedicated to Hercules attest. It is from here that the stone for Diocletian’s palace in Split was extracted.

The primary building unit is a single-cell house with gabled roof. It is used in secular as well as in sacral architecture. From this type other buildings developed, with additional floor(s), more complex ground plans and more rooms.

Beside roofs, many other elements and objects are made of platy limestone

Beside roofs, many other elements and objects are made of platy limestone: shelves, chimneys, areas for the collecting and directing of water into cisterns, even beehives. One special feature is the use of a lime coating on stone roofs to protect the roof and disinfect collected rainwater at the same time.

From the central Dalmatia region, 1 object from Hvar, 1 from Slatina, 2 from Ume (village Tugare), 1 from Trogir, 1 from Brač and 1 from Šolta were studied.

Three objects/complexes that reveal a broad spectrum of regional architectures were chosen as showcases – the Trogir cathedral, the monastery in Blaca and the village of Grohote in Šolta. The Romanesque cathedral in Trogir is a triple-nave basilica built in the 13^th century by the master Radovan, and is a masterpiece of local stone masonry (see Annex 3.I.6.1).

Ruića dvori in the village of Grohote on Šolta is a typical example of residential island architecture (Fig. 3.12).

The Blaca monastery on Brač took on the form it has today during the 8^th and 19^th centuries, and consists of different residential and commercial objects. Today it is protected, renovated and used as a museum.

Southern Dalmatia (Appendices 3.I.7 and 3.II.4)

The rural areas of the Pelješac peninsula and the island of Korčula, especially auxiliary objects (stables, kitchen buildings) have remained intact to a large extent, allowing rare insight into the original appearance of the vernacular architecture. They also represent an opportunity to document their current state and provide a prototype on which future reconstruction actions can be based. Such a broad approach is not just a way of conserving lost heritage, but given today's changed economic reality (like rural / eco / sustainable tourism), could guarantee a connection between past traditions and future development.

On the island of Korčula, the best stones for various distinctive architectural elements and decorations has been extracted from quarries on the islands of Vrnik and Sutvara, from the Kamenjak cape, the south-eastern part of Korčula and from the Pelješac Canal.

From southern Dalmatia, on the island of Korčula, and on the Pelješac peninsula the buildings from Donja (3) and Gornja Nakovana (1), Vela Luka (2), Blato-Gospe od Polja (1), Miletić (2), Postrana (2), Pupnat (1), Salapućeva njivica (1), Smokvina (1), Dub (1), Gornja Njivica (1) and Zanavlje (1) were documented.

Three examples were studied as showcase examples: the homestead “U Cvitka” from Donja Nakovana on Pelješac, the complex of single-cell houses from Postrana (Fig. 3.13), and a stable from Vela Luka, both from the island of Korčula (see Annex 3.I.7.1).

Platy limestone as a cheap and easily accessible material was mainly used to cover roofs, and in consequently became a widely recognisable element of karstic architecture up until the first half of the 20^th century. But the use of inexpensive and readily available materials such as asbestos boards and tiles, the look of the landscape together with entire hamlets has been degraded and alienated from tradition. Also, the skill of manually extracting platy limestone has been abandoned, and despite the long tradition of stone processing on the island of Korčula only a few people who still practice this long forgotten tradition still exist.

Herzegovina (Appendices 3.I.8 and 3.II.5)

The long tradition of building with platy limestone began in Herzegovina as early as prehistory, when it was used as a building material in hill forts and as a part of grave architecture. The only archaeologically confirmed Roman-era quarry from Herzegovina is in Bandera, near Zvornik, outside the project area. From eastern Herzegovina quarries from Medieval times are known, mainly connected to the extraction of stones for massive gravestones (Biljezi/Stečci).

A number of old, active or abandoned quarries of platy limestone are known from the region (Mostarska Vrata, Crnopod , Zvirovići, Podveležje, Žovnica, Miljkovići, Dobrič, Kolojanj, Tepčići, Grabova Draga), which are/were used mostly in local building activities.

Platy limestone is most frequently used as a roof covering, the most common of these being the gabled roof; a four-sided roof is typical for oriental/Ottoman architecture. Different techniques are employed, the most taking the “husk” shape, with stone plates laid diagonally. Natural plates appear in a variety of sizes (from 20x20 cm to 1 m²), thicknesses and colours. They are laid without binder or with mortar, with a covering of plates in one, two or even three layers.

From Herzegovina 24 buildings: 5 from Mostar, 4 from Počitelj (Fig. 3.14), 5 from Blagaj, 5 from Stolac, 5 from Ljubuški were documented. In the second phase of the project, five objects were chosen as selected examples.

All selected showcases in Herzegovina are located in the south, with the northernmost location in the city of Mostar (Map 3.1). The selected examples cover different types of architecture: residential house, commercial complex, fortification and religious object. The stone roofs of all are in good condition, most of them renovated in the 20^th century or even more recently. The platy limestone comes from the Podveležje quarries, or from other local sources. They are all protected with the status of national monuments (see Annex 3.I.8.1).

Bišćević House, from the centre of Mostar (Fig. 3.15), is a traditional homestead built in the Ottoman period (late Middle Ages). Its roof of platy limestone from Podveležje was partly reconstructed in the 20^th century and is today in a largely good state of preservation. Gavrankapetanović Tower is part of the Ottoman fortifications of Počitelj, built in the 17^th to 18^th centuries. The stone roof was renovated in 1971 and again in 2001. Velagić Mill, in Blagaj, is a commercial complex from Ottoman times. The roof was reconstructed in the 20^th century. The Čaršijska mosque from Stolac is a religious building that was fully renovated in 2006.