Sean McKinley is a retired 70-year-old in Wilmington, Del., who loves golf.

He took a golf vacation to Pebble Beach on Sept. 5, 2000, and returned to play again on Aug. 31 of this year.

But it’s what he did in the 11 years between those two rounds at Pebble Beach that makes him the most enviable 18-handicapper in America.

McKinley received a coffee table book for Christmas in 1999 called, “The Top 100 Courses You Can Play,” by Golf Magazine senior editor Brian McCallen. While flipping through it, the soon-to-be retired engineer dreamt up the fantasy of playing every course on the list.

His first round on his checklist was that trip to Pebble Beach in 2000, the No. 1 course according to the book published in 1999. McKinley thoroughly enjoyed his round there, but his favorite course in the forest was actually Spyglass. He ranks Spyglass only behind Bethpage Black No. 2 in New York, which he managed to play four times.

While anyone can play Bethpage, securing a tee time usually comes at a steep price. The green fees at the state park golf course are an absolute bargain at $65 for residents, and a still reasonable $130 for non-residents, but the currency for locking up a tee time is often hours of sleep donated while waiting in the parking lot overnight.

But McKinley figured out through a friend that he could make a tee time by calling the pro shop directly — via a hospital phone. A friend’s sister booked the tee time from the hospital, which

evidently has priority over the flood of calls trying to get through.

McKinley’s first round at Bethpage Black was a 99, but he felt much better about how he played after watching the 2002 U.S. Open there.

“The toughest course was Bethpage Black, but it was also the most enjoyable,” McKinley said. “It was incredible, but it was just brutal.”

The best value on McKinley’s 11-year golf odyssey? That would be Pinion Hills in Farmington, N.M., which McKinley remembered being only $50-60.

That brings up the question of how much this pilgrimage cost.

“Somebody asked me that,” McKinley said. “I just spent $14,000 for this trip to Pebble, including airfare and hotels. I think that’s the most expensive. I never did figure it out, but I spread it out over 10 years. I put a lot of miles on my car.”

His latest trip to Pebble Beach included rounds at Pasatiempo (No. 17), Bayonet, and Spanish Bay (No. 45), the final course left on his list. As McKinley walked up the 18th fairway at Spanish Bay on Aug. 30, he was serenaded by the bagpiper, and followed by a gallery of his friends and family. Everyone in his gallery wore green hats that read, “McKinley Golf March 1,800 Holes,” but his journey was much longer than that.

McKinley organized his trips by picking off corners of the country, and mowing through the best courses in that area like a John Deere. When he went to Oregon to play Pumpkin Ridge (No. 13), Sunriver (No. 15) and Sandpines (No. 72), McKinley made sure to detour to Bandon and play three courses that were built after his book was published — Bandon Dunes, Pacific Dunes, and Bandon Trails.

McKinley also did the same when he traveled to Blackwolf Run in Kohler, Wis., making sure to get in rounds at the newer Whistling Straits, which hosted last year’s PGA Championship.

McKinley’s scoring average at the top 100 courses was 94.4. His best round was an 85 at Stonehouse in Virginia, while his worst was a 108 at Karsten Creek in Oklahoma.

“I got down to 15 or 16 handicap, but I never could do much better than that,” said McKinley, who plays three to four times a week at Cavaliers Country Club in Newark, Del. “When I was working, it was more a matter of when I could get out. I certainly didn’t play the amount of golf I do now. As I’m reaching 70, the ball just doesn’t go as far as it did.”

And then there’s the golf he’s played outside the States. In 2002, McKinley went on a golfing trip with two sons and his brother, playing the gauntlet of courses at St. Andrews, plus Kingsbarn, which he called, “the greatest golf course I’ve even see in my life.”

For his 65th birthday, McKinley took a trip to Ireland, where he got to play Royal Portrush.

Which begs the questions: What’s next for McKinley?

“That’s what my family has asked me,” he said. “I don’t know. I need some objectives, I need something. They asked me about the Top 100 in the world. We’ll see …”