There is nothing like it in North America and while certainly there may be other examples, I am aware of only one other 18 hole example in the entire world--arguably the most iconic course in the world, The Old Course at St. Andrews, was built to be played in two directions.
I was scheduled to play The Loop in August, 2016 along with several friends but an unfortunate medical issue caused me to surrender my slot. My friends who did get to sample the course reported it was not quite ready for public play as there were many areas of the course that lacked grass.
Fast-forward to the last week of August, 2018 when I finally was able to see the course for myself.
I was a part of a group from Coyote Creek Golf Club in Fort Wayne, IN who scheduled a three day, two night stay at Forest Dunes Resort. We would stay in one of the cottages onsite and play one round of golf on the Forest Dunes course each day from Monday to Wednesday. And I, as the only walker in the group who had yet to play The Loop course, would add a morning round on Monday and Tuesday before joining the others for the afternoon round.
My round at The Loop's Black Course was scheduled to begin at 8:03 A.M. Monday. We were staying in Mt. Pleasant, MI and severe storms began during the overnight hours. I left the hotel at 6:00 A.M.for the 80 minute drive and drove at a reduced speed through persistent thunderstorms nearly the whole way. When I arrived at the resort, I immediately checked with the pro shop to determine the likelihood I'd be able to play. Having already played the Forest Dunes course several times, my plan was to forgo rounds on that course if necessary to be sure I could play both the Black and Red routings of The Loop.
I had the good fortune of being the only scheduled round on the course until 10:30. I knew I could walk the course in two and a half hours and still make the afternoon tee time with the rest of the group. So that gave me some time to allow the rains to subside a bit.
The Loop
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Why the need for a flat piece of relatively open land? Doak explained that hilly land could lead to blind shots in one direction or the other and trees out of play in one direction may be an issue in the other direction. As it turned out, there is only one hole where a shot to a green is blind and that is the second shot into the 18th hole of the Red course.
Key to the design are The Loop's greens which are accessible from 360 degrees. Because of this, there are no crazy undulations or contours.
The Loop's Black routing plays clockwise and the next day, its Red routing uses the same greens and plays counterclockwise. These courses, built on well-draining soil are "walking only."