Since the creation of the LOOP, efforts have been addressed to keep and develop a continuous monitoring programme. Lake Redon still stays as one of the flagship sites for this long term ecological research. But since 2004, works have also started in order to extend the monitoring of surface high mountain waters from the level of a single lake to the whole catchment. Crucial to this has been the participation in the research programme of the Spanish National Parks Network and, in particular, the collaboration with the Aigüestortes i Estany de Sant Maurici (AESM) National Park. The starting point was a project run in 2004-06 aimed to define the monitoring protocols to use one large catchment (the St. Nicolau Valley) in the AESM National Park as a long term ecological research and monitoring site, focusing on surface waters as the factor integrating and reflecting the environmental changes in the catchment. Since 2008, the National Park hosts a long term ecological research node (LTER-Aigüestortes) associated to the LTER-Spain, LTER-Europe and ILTER networks, in which the LOOP participates together with teams from other institutions.