Really delighted to stumble across this superb online resource. It’s The Port Lovers’ Forum map of Douro Quintas.
For anyone like me who has been to the Douro a number of times, this is a brilliantly useful map. If you travel around the region by road, it’s really easy to be disoriented. Travelling by river is the best way of understanding what’s where. Maps like this really help bring the geography of this stunning wine country to life.