Everything that we have ever seen, experienced, heard or felt stays with us forever. We might not remember it, but our subconscious does.
There are landscapes that stick in our memory or in our hearts once we have seen them. The most memorable moments in our lives when having a blast will bring out landscapes connected to those moments. Those memories can be triggered by the sound of train, river, plane or voice; smell of rain, fall, fire or water; vision of trees, fields, mountains, buildings or roads.
We cannot control the visions when the trigger pulls. It happens automatically even before our mind starts processing it.