At perfect sunny weather conditions, international guests participated in a study tour on solar thermal and biomass district heating systems in Denmark on 21-23 September. 27 participants from Serbia, Bosnia and Herzegovina, Croatia, Macedonia, Slovenia, Austria, Germany and Denmark saw in best practice examples how heat from the sunlight and biomass can provide sustainable energy for the operation of district heating grids. The study tour was organised in the framework of the CoolHeating project, which is supported by the Horizon 2020 programme of the European Union. CoolHeating, coordinated by WIP Renewable Energies, Germany, promotes the set-up of small modular renewable heating and cooling grids in South-Eastern Europe up to the investment stage. PlanEnergi from Denmark is specialised in such heating grids and organised the study tour.