The Bahrain Pearling Path: Urban Planning, Structural Investigation and Design of the Strengthening Interventions

  • Marco Motisi
  • Filippo Casarin
  • Gionata Rizzi
  • Franco Pianon
  • Alessandro Zamara
  • Lucia Gomez-Robles
Part of the RILEM Bookseries book series (RILEM, volume 18)


The Bahrain Pearling Path (or Pearling Testimony) is a cultural heritage site inscribed on the UNESCO World Heritage List in 2012. The site consists of seventeen buildings in Muharraq City, three offshore oyster beds, part of the seashore and the Qal’at Bu Mahir fortress on the southern tip of Muharraq Island, from where boats used to set off for the oyster beds. The listed buildings include residences of wealthy merchants, shops, storehouses and a mosque. The site is the last remaining complete example of the cultural tradition of pearling and the wealth it generated at a time when the trade dominated the Gulf economy (2nd century to the 1930s, when Japan developed cultured pearls). In the framework of the restoration activities undertaken by the Bahrain Authority for Culture and Antiquities (BACA), an effort is currently ongoing for the re-use of the existing buildings preserving their structural behavior, also according to the ICOMOS ISCARSAH restoration principles. An extensive investigation campaign, preparatory for the successive strengthening interventions, was then carried out in 2017, aiming at defining the main mechanical features and characteristics of the stone masonry walls (composed by the locally named “coral stone”) and of the timber floors, originally (and still today) composed by round mangrove logs. The paper refers on the investigation campaign outcomes and the subsequent design criteria for an effective, however respectful, strengthening intervention.


Bahrain pearling path Coral stone Gypsum mortars Material testing 



The Authors would like to acknowledge the Bahrain Authority for Culture and Antiquities (BACA), the public body in charge of the conservation and development of the Pearling Path and overseeing the culture sector in the Kingdom of Bahrain, which financed the technical activities reported in the paper.


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Copyright information

© RILEM 2019

Authors and Affiliations

  • Marco Motisi
    • 1
  • Filippo Casarin
    • 2
  • Gionata Rizzi
    • 3
    • 4
  • Franco Pianon
    • 5
  • Alessandro Zamara
    • 5
  • Lucia Gomez-Robles
    • 6
  1. 1.VeniceItaly
  2. 2.Expin srl, Spin-off of the University of PadovaPaduaItaly
  3. 3.ICCROM, M.A.YorkUK
  4. 4.Studio Architetto RizziMilanItaly
  5. 5.Studio Pianon e AssociatiVeniceItaly
  6. 6.Pearling ProjectBahrain Authority for Culture and AntiquitiesManamaKingdom of Bahrain

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