I find the old courses are much easier to walk. In my area anyways, the newer course are built on larger acreage. Lots of old farms and such. So, the proximity from green to next tee boxes is quite far. It meanders through woods, and water. So, while the ambiance and scenery is fascinating, the walk,especially in the heat of summer, can be overwhelming. But, I do walk my home course once or twice a week. It is an old Devereux Emmet (1926) design, and the tee boxes are a short walk from the greens. I did walk Bethpage Black at 57 years old, because there are no carts. That was a workout.