The picture was taken today in the Netherlands. Can you identify this plant species?
Like @skymningen thought, this is a Clematis. However, the only wild Clematis in the Netherlands is Clematis vitalba, that has much smaller flowers (about 2 cm diameter) see "Heukels' Flora van Nederland" (the official Dutch flora) and here.
So you have photographed a plant that "escaped" from a garden. Most garden Clematis are hybrids from Chinese or Japanese origen. As there are about 300 species and new hybrids constantly being produced, the likelyhood of finding it's name is low. https://en.wikipedia.org/wiki/Clematis