Nicholas Mellor is the founder of 4DHeritage. 4DHeritage is pioneering the use of agile, immersive approaches to enable communities to document and monitor fragile ecosystems and endangered heritage sites. This recognises that this heritage be it natural or built is often vital to their identity and livelihoods. In doing so it is an opportunity for the people of those communities to share their stories.
Youssef Mekael is an Architecture master's student in Politecnico di Torino, currently working on his final thesis where he is studying the effect of new technologies in construction on the architectural heritage of the oases in the Sahara desert. Siwa is the case study for his research not only for its unique architecture but for its special place in his childhood memories during his father's work in the Oasis.
What is so special about this Oasis? The Siwa Oasis is a fertile depression 300km southwest of the Mediterranean, and 170 km east of the Libyan border. The fortress of Shali was built during the Mamluk period, around 1200 AD, on a hill, to ward off Bedouin attackers. Siwa is now one of the last surviving oases on the planet, an environmentally fragile ecosystem supporting a unique cultural and architectural heritage. Nowhere else in Egypt can one find buildings in rock-salt and clay, or a population whose first language is Berber.
Over the years, as Egypt became more secure and the Bedouin attackers con-tained, Shali was steadily abandoned in search of more spacious areas, prompting the fortress’ steady deterioration. Although part of the fortress city is under the jurisdiction of the Ministry of Antiquities, many of the old houses of Shali are still owned by Siwan families, most of whom now reside in other parts of the Oasis. Although income levels tend to be low in the Oasis, iit is rich in its pristine environment and its architecture, language, music, decorative and folk arts.
Nicholas: Can you describe what Shali looked like through the eyes of a child?
Youssef: Shali was the dream playhouse for a child, a giant hill full of ruins where the imaginary stories have no limit. Racing to the top of shali to catch the sunset is an unforgettable memory.
Nicholas: What was your father doing in Siwa?
Youssef: He has been practicing architecture till today in the oasis. He designed in the last 30 years several projects of eco-lodges and other public buildings. Also, the restoration of the Shali fortress and its 2 mosques, and a third mosque that this next to the Oracle of Amun. The beginning of his journey in Siwa was to rediscover the kershif architecture and its techniques.
Nicholas: This was an extraordinary project in terms of its scope, combining socio-economic and cultural heritage preservation project aiming to stimulate Siwa's economy by improving the Oasis' international standing as a leading eco-tourism destination. It is also sought to
improve the living conditions of Siwans by offering them employment opportunities for sustainable economic growth. From your perspective what are the most striking differences before and after the conservation of the Shali Fortress?
Youssef: The most striking differences are the appearance of the streets, the streets were not that perceived in the past. Walking in the fortress’ narrow streets is an undescribed feeling, where you can experience walking in the old city where it’s written in the books of the 18 and 19th century.
Nicholas: One of the many remarkable features of oases is that traditionally everything had to be built from materials that were locally available, be it wood, rocks or earth. What is a kerchif?
Youssef: An unusual material made of salt crystals with impurities of clay & sand. The blocks of irregular shape taken from the salt crust that surrounds the salty lake, without any attempt of regularization are cut into smaller blocks and utilized in the masonry with a mud mortar. A unique thing about Kerchief is that it's reusable, most of the materials used for the revival of Shali fortress were the same that were used to build it about 1000 years ago.
Nicholas: Why is kerschif unique to Siwa?
Youssef: As far as I know, Siwa is the only place where salty rocks are used as a traditional material for construction.
Nicholas: We heard from Richard Hughes of Arups just how complex it is to work with earth in a way that transforms it from ordinary soil or even mud into a material from which great buildings can be created. What gives the kerchif its strength?
Youssef: During the drying process of this particular kind of mortar, a strong connection is established between the blocks and the mortar due to the crystallization of the NaCl inside the mortar itself, giving rise to a sort of monolithic conglomerate.
Nicholas: The chemistry or dare I say, alchemy of this process is often embedded in historical practices and traditions associated with intangible rather than tangible heritage. You described the process of construction as more like a dance than a manufacturing process. Can you describe 'the dance' of the mason? And why is this significant from both a technical and cultural perspective?
Youssef: The construction of the wall proceeds rhythmically like a dance directed by the (Meaalem) master, the construction process required the work of three people, the (Meaalem) master, and two assistants one responsible for the kershif blocks and third for the mortar.
Nicholas: What are elements going into the building?
Youssef: Besides the kerchief blocks, palm trunks are used to constitute the supporting structure of the floors/roof at different levels, olive wood is commonly used for lintels, stairs, the supporting structure for the roof in the narrow spaces, a corridor for example.
Nicholas: How are these other materials prepared?
Youssef: Each element has its tips and tricks to increase its durability and life. The palm trunks are cut from October to December as it’s not the season when too many parasites and pests are living, to prevent them in the future, the trunks are immersed in the salt lake for a week then left to sun-dry.
Nicholas: How is it combined with modern building materials?
Youssef: One example of a combination is in the toilets. Kerchif suffers when there is high humidity therefore this makes it hard to host modern toilets with water circulation. The toilet room is built using fired bricks or limestones with a layer (20-30cm) of kerchif from the outer skin. This layer is not for preserving the vernacular style only but for adding an insulation layer to the wall.
Nicholas: What are the greatest threats to kerchif conservation?
Youssef: The greatest threats to kerchif are the limited spaces allowed to build on. The thickness of the kerchif wall can reach one meter, with this limited surface area, it’s not worth wasting space, and the best option will be the white toob (limestone).
Nicholas: If there is one image that sums up this building material, what is it?
Youssef: I have chosen 2 pictures, the first one is myself as a child learning about my father's work . The second is a picture shows how the construction of the wall that proceeds rhythmically like a dance directed by the (Meaalem) master.
Nicholas: What do you aspire to do in the future?
Youssef: I would like to work in the field of upgrading and improving traditional architecture allowing it to host modern life’s activities and technologies and to help the communities with such an architectural style to sustain their environmental ecosystem and grow sustainably.
To learn more about the restoration programme of the Shali fortress, see the video below.
The project was funded by the EU and implemented by Environmental Quality International with support from LSN's 4DHeritage initiative to 3D model the site and use of immersive storytelling to share Siwa's rich heritage. This was part of the EU-funded Inclusive Economic Growth Program (IEGP) which was set up to promote economic recovery in Egypt by leveraging Micro, Small and Medium Enterprise (MSME) development and cultural heritage for inclusive growth and the creation of decent jobs.
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