While walking on the tracks you'll come to a large stone bridge on the right that crosses a dam. Walk over the bridge and enter the house directly in front of you by following the path to the right of it. You will need to explore the entire house and its 3 floors. Be sure to inspect the picture upon entering the house and listen to all of the dialogue in each room by simply walking around them.
The achievement will unlock when you reach the attic near the table with the books.