On October 4th, 2012 the Municipality of Thiva signed the constitutional charter of the Network of Twinned Towns with Lakes.

This is a very important institution that signifies the environmental care that characterizes Thiva, but also favors ecological – hiking tourism.
The objectives of the network are to inform and raise awareness among citizens and businesses on issues concerning the protection of water resources, especially lakes, the exchange of management experiences with other municipalities in Greece and the European Union, and the creation of a framework for the healthy development of lakeside areas.

The Network of Cities with Lakes includes the two natural lakes Yliki and Paralimni, belonging to the Municipality of Thiva and Orhomenos, which are two very important natural water reservoirs of Central Greece and collect the waters of the watershed of the Boeotian Cephissus, from the river Spercheios and further south. The beautiful landscapes of both Yliki and Paralimni are an attraction for Greek and European travellers who love the aquatic element, the observation of the natural landscape and outdoor activities.

The Network of Cities with Lakes includes the two natural lakes Yliki and Paralimni, belonging to the Municipality of Thiva and Orhomenos, which are two very important natural water reservoirs of Central Greece and collect the waters of the watershed of the Boeotian Cephissus, from the river Spercheios and further south.