The best protected parts of the Sonian Forest are part of the UNESCO World Heritage List, as part of a group of a total of 94 exceptional beech forests in 18 European countries. The World Heritage Committee has recognised these forests as a joint testimony to the exceptional evolution and impact of the beech ecosystem in Europe since the last Ice Age.

In 2007, UNESCO had already recognised pristine beech forests in Ukraine and Slovakia. This limited group was expanded in 2011 to include German beech forests. Since 2017, the group was further completed with beech forests in Albania, Bulgaria, Italy, Croatia, Austria, Romania, Slovenia, Spain, and the best protected parts of the Sonian Forest in Belgium.

In 2021 this series was extended with 6 additional States Parties: Bosnia & Herzegovina, Czechia, France, North Macedonia, Poland and  Switzerland.

This extension adds 15 new protected areas to the network. And more precious forest areas in other countries could follow. The entire World Heritage Site comprises the few remaining European primeval beech forests and centuries-old European beech forest areas, which are almost unaltered by humans.

This World Heritage series is currently the largest serial World Heritage property. A steadily evolving Masterpiece without borders.

World heritage recognition based on rigorous international selection

The enlargement is the result of an international research project. Among other things under consideration were the location, the soil, the climate, and the genetic diversity of the beeches. Based on these elements, Europe was divided into 12 regions, each with its own specific characteristics. Belgium belongs to the region of Atlantic beech forests. For the Atlantic region, only the Sonian Forest has been included in the group.

Forest reserves as a window to the primeval forests

Not all the Sonian Forest has been recognised as a world heritage site. Specifically, there are five areas designated as integral forest reserves, which are located in the Joseph Zwaenepoel reserve, Grippensdelle and the Ticton forest reserve. These parts of the Sonian Forest are no longer under any management and are characterised by a very complete composition with exceptionally old trees and an exceptionally rich biodiversity. In this way, this ‘chain’ of world heritage can serve as a window onto what primeval forests and ancient forests in Europe look like. This heritage tells the story of the beech, a single species that made up the primeval forest of an entire continent. After the last Ice Age, beech has moved step by step from Central and Southern Europe to the North, and today dominates the natural forests of most of Europe. This is unique in the world.

Unique story for our country

The recognition of natural world heritage is also unique to our country. Previously, all the world heritage that our country had been rich in is man-made. In other words, it is catalogued as the ‘cultural’ world heritage. The Sonian Forest is one of the last untouched pieces of forest and is therefore registered as a ‘natural’ world heritage site.

In addition, the Sonian Forest is the only forest located in Brussels, Flanders, and Wallonia. That is why a joint ‘structural vision’ has been drawn up, within which this designation as a world heritage site has also come about. This dossier is the result of very close cooperation between each of the three regional forest managers and each of the three heritage services. Since 2014, these six administrations have been working closely together both within our country and within the European beech forest network. Recognition as a world heritage site is also a recognition of this cooperation and can only strengthen the ongoing coordination of conservation and management.

UNESCO secretariat for old beech forests in Belgium

Moreover, since 2020, Belgium has assumed the role of UNESCO secretariat for old beech forests, for a period of four years.