Soletanche Bachy, world leader in foundations and soil technologies
Follow us
Choose your language

November 7th, 2022

ZETAS works on restoration of Topkapi Palace, the former residence of the Ottoman sultans

Zetas has been awarded a contract by Eril Architecture to upgrade the retaining walls of Gülhane Road, within the Topkapı Palace complex in the heart of Istanbul.

A brief history…

Topkapı Palace is located on the tip of the Sarayburnu (Seraglio Point), a promontory overlooking the Golden Horn, where the Bosphorus Strait meets the Sea of Marmara. Topkapı Palace was first built in 1459 on the order of Sultan Mehmed the Conqueror and the complex then expanded over the centuries, including major renovations. From the 1460s until the completion of Dolmabahçe Palace in 1856, it served as the administrative centre of the Ottoman Empire and was the principal residence of its sultans until the 17th century.
After the end of the Ottoman Empire in 1923, Topkapı was transformed into a museum by a government decree dated 3 April 1924. Topkapi Palace, which still serves as a museum today, was recognised by UNESCO as a World Heritage Site in 1985.

Topkapi Palace, UNESCO World Heritage

Photo by Nima Aksoy on Unsplash


Context and scope of work

The Topkapı Palace restoration project was gradually launched following the collapse of a wall in Istanbul’s historical Gülhane Park (part of Topkapı Palace) in 2016.
In 2019, Zetas successfully completed the first stage of the Topkapı Palace upgrade works, which were carried out to improve the seismic-resistance of the walls on the hillside, which are also very close to the current project site.
For the second phase, Zetas is working as a subcontractor for the construction of micropiles with anchors and permanent nails, in order to stabilise the slopes of the Gülhane Road in Topkapı Palace.


  • Stabilisation de pentes via la réalisation de micropieux, de tirants et de clous permanents
  • Mise a niveau des murs de soutènements au palais de Topkapi
  • Travaux d'amélioration de sols au palais de Topkapi à Istanbul

Our teams will install micropiles, with a diameter of Ø225mm to a maximum depth of 20.0m, at various levels along the Gülhane Road. The project also includes preparation of the platform, construction of permanent and temporary retaining walls, anchors and permanents nails. High quality steel materials (SAS threaded bar systems) will be used for this important project.

Zetas began logistics and construction work for the Gülhane Road micropiles immediately after signing the contract in October 2022 and the project is expected to be completed within six months, by the end of March 2023. 

Share the news

Go to Top