UNESCO – PORTUGAL

In June 2024, the municipalities of Almeida, Marvao and Valença do Minho presented an official request for inscription on the UNESCO World Heritage List for the Raia fortifications. This handover took place in the presence of the Mayor of Valença, José Manuel Carpintaria, the presidents of the municipalities of Almeida and Marvão, António Machado and António Vitorino, respectively, the President of the National Commission of UNESCO, Ambassador José Moraes Cabral, the Vice-President of ICOMOS Portugal, Ana Paula Amendoeira, the coordinator of the application, Professor João Campos, the president of the Vauban association, Alain Monferrand and other technicians from these three municipalities involved in the application.

At our 2024 IFC annual meeting in Namur, it was decided to present a motion of support from the IFC for the candidacy of the Raia fortresses in Portugal for inclusion on the UNESCO World Heritage List. The IFC Board was entrusted with drafting this motion and sending it to the Fortifications Interpretation Centre and to Almeida, who are supporting this entire candidacy in a network. You will find this letter of intend below, which we invite you to relay and adopt.

ALMEIDA – MARVAO – VALENCA DO MINHO CANDIDATE TO UNESCO

The International Fortress Council (IFC) hereby strongly supports the candidature of « Fortalezas Abaluatadas da Raia » in Portugal for UNESCO World Heritage status, which is being promoted by the municipalities of Almeida, Marvão and Valença do Minho.

« The Portuguese heritage of bastioned fortifications of the seventeenth and eighteenth centuries is considerable. Covering the internal borders with Spain as well as the coast or the Portuguese colonies, this fortified heritage includes fortifications that are still intact and very well preserved. In Portugal, after those of Evora and Elvas, already classified by UNESCO in 1986 and 2012, we can mention in particular, those of Almeida, Marvao, Valença do Minho. « 

The proposal presented by Portugal is based on very solid historical and architectural documentation, the result of numerous studies coordinated over the years in the three cities by the teams of Professor Joao do Campos and his Centro de Estudos de Arquitetura Militar (Centre for Military Architecture Studies – CEAMA) which is located at the Santo António outer gate of the bastion in Almeida.

The importance of this classification is based on its heritage value and relevant as a testimony to the history of Europe: After the restoration of Portugal’s independence between sixteen forty and sixteen sixty-eight (1640-1668), the biggest financial investment was concentrated in renovating the fortifications of towns and cities located near the border. In addition, it became necessary to hire foreign military engineers – mainly Dutch and French – who mastered the Modern Fortification. In 1647, the Military Fortification Class was formed to train Portuguese military engineers to continue the works and projects during all the seventh century.

The three candidate fortified cities are emblematic of the « Raia », a new fortified system designed to protect the century-old border of Portugal with Castile and which in its design and construction presents great analogies with the devices designed in France by Vauban such as the « pré carré » facing the Spanish border in Flanders.

It is very important that most of this Fortifications could underline the great interest of the possible international classification of the network of seventeenth-century fortifications on the border between Portugal and Spain. In a first phase, refers to Almeida, Marvão and Valença, but also on others that may be added to them (and potentially cross-border), once the nature of exceptional universal value is considered to be part of the network.

For all these reasons and noting in particular that the candidacy, collectively supported by local authorities and their elected representatives, has set itself the objective of building a network to which other cities and fortifications can be added, the IFC General Assembly voted unanimously in favour of supporting this candidacy from Portugal during the annual meeting in Namur (B) in 2024. The IFC Board will send this motion to all his 15 members to support this candidacy.

 Andreas Kupka M.A. (Chairman), Marc Gayda (vice-chairman), Jeroen van der Werf (Gnl Secretary)

Several national associations have also offered their support for this application with official letters. Notably, we can mention : APAC (Portugal), Association Vauban (France), DGF (Germany), FFGL (Luxemburg),…

RESILIENT FORTRESS

Application:

Ancient and modern fortifications were designed by the best available military engineers and designers. They were places of technological and logistic innovation, planned to be autonomous in case of siege. These places of defence and attack can educate us on solid building techniques, on economic use of materials, as well as on water management. From the 16th to the 20th century, the architecture of war includes massive amounts of earthworks, spread to wide areas, which today are ecological reserves much needed in the preservation of biodiversity.

European Project

Erasmus + project named Resilient Fortress -application, presented by the Governing Body of Suomenlinna as lead partner with Stichting Monumentenbezit for the fortifications of Naarden (NL), Centre des monuments nationaux for the stronghold of Mont-Dauphin (F) and EFFORTS, European Federation of Fortified Sites (EU & B) with experts from France (Atelier d’Architecture Philippe Prost with Anibes and St Tropez) and Italy (Studio Architettura Meneghelli), Sweden (Bomarsund) was chosen to be funded in June 2024.

A symposium was organized at Naarden on the 4-7 of May with a meeting on the 6th to present a part of the results of the project and the contribution of a lot of specialists from 5 countries (Finland, France, Netherland, Sweden, Italy)

All of this work allows for a series of reflections and constraints that are imposed on restorers and managers of fortified sites.

THE REPAIR OF DISORDERS AND THE RESTORATION OF WORKS

Apart from the restoration approaches that must meet the requirements of the Venice Charter of 1964, supplemented in 2000 by the Krakow Charter, which emphasizes the importance of keeping remarkable buildings functional (without affecting their layout or decor), it also deepens the principles and broadens their scope.

Taking into account the fauna and flora : Often featuring significant open areas, fortified spaces and their neglected areas host a fauna and flora that must be inventoried to identify elements that are dangerous for the conservation of monuments (notably with the development of roots that loosen stones and bricks) as well as those that should be preserved, or even prioritized.

The fight against climatic éléments : A change in climate is particularly evident on fortifications at high latitudes (Finland) or at high altitudes. At Suomenlinna, it is noted that the periods of drought are more significant and longer. In addition, there are alternating periods of freezing that are no longer continuous during winter and are followed by snowfall and rain, which damages the faces of the bastions.

The fight against erosion : Soil erosion is comparable to the erosion of masonry structures. If the grassy surface of a rampart or parapet has dense growth and there is a sufficient slope, the vegetation acts as a waterproofing agent. Rainwater only moistens it from the surface. But if the vegetation is worn and eroded, water also moistens the soil. The fortifications have masses of earth and sand to protect them from artillery fire. If this volume is loaded with water, its weight doubles. When the wet soil freezes, the pressure of the ice is enormous and can cause dangerous collapses.

The choice of materials : The restoration work should be preceded by an analysis of the production sites of the initial materials to understand the choices made during the initial construction. This is the approach that was initiated by Mont Dauphin, which thus identified all the extraction sites of the stones and materials used during the construction of the square and thus located the materials to be used during the restorations or at least identical materials.

THE MAINTENANCE AND CARE OF SPACES

Maintenance : The maintenance of fortified sites poses numerous problems. « The cultivation » of lawns in order to later harvest them in slabs raises the issue of production (where to produce them and how to protect them from trampling as soon as they are laid? To what extent can this production be ensured?). Restoration periods and construction zones also impose access restrictions.

Monitoring : The monitoring of the vegetation condition and the effects of maintenance must be continuous. One could speak of a so-called observational maintenance. Moreover, through continuous monitoring, maintenance methods can be adjusted according to the effects caused by climate change.

The management of overtourism The overcrowding of certain points at heritage sites raises difficulties. The trampling and the creation of pathways outside marked trails, or the incivility of visitors contribute to the creation of disorder or modifications of spaces.

CONCLUSIONS

Despite fundamentally different sites, the working group found many common issues. Sharing experiences often allows for saving time in searching for solutions.It also appears that knowledge of the conditions for constructing works, however, until the mid-20th century, engineers worked for several countries, bringing their methodologies and knowledge, which also partly explains the identical nature of the observed disorders and the use of identical materials, often relying on wood, quarries, sands, or lime produced not far from the completed works..

You can you can refer to the booklet we made about the project.

Program and objective (in french and english) :

https://www.monuments-nationaux.fr/actualites-du-cmn/projet-europeen-forteresse-resiliente

the final report is available for download at: https://monumentenbezit.nl/publicaties/publicatie-resilient-fortress/

All the informations about the project : Resilient Fortress, report, Erasmus + 2025, 124 p.

. Resilient Fortress, Antibes, Erasmus +, 2025, 8 p.

. Resilient Fortress, Mont Dauphin, Erasmus + 2025, 12 p.

. resilient Fortress ; Naarden, 5-7 mai 2025, Erasmus +, 12 p.

. Resilient fortress guidelines, Erasmus + project, 2025, 12p.

. The program and objective in video (french and english) on the website :

https://www.monuments-nationaux.fr/actualites-du-cmn/projet-europeen-forteresse-resiliente

.https://www.monuments-nationaux.fr/formation-expertise/nos-expertises/projet-europeen-forteresse-resiliente

. The publications of Resilient Fortress are available on the website :

https://monumentenbezit.nl/en/publicaties-onderzoek-monumenten/