It was after I'd played my third consecutive round of golf last Thursday that I began to worry. I couldn't straighten my fingers. The sun was so bright that I could feel the melanin percolating to the surface of my skin like globules in a lava lamp. And still I had four rounds ahead of me.

That it was miniature golf I was playing should in no way diminish my achievement: tackling seven of Ocean City's toughest midget golf courses in a single day.

I had planned my assault carefully. It would be suicide, I'd decided, to play all of O.C.'s 20 or so courses successively. Instead, I focused on the seven courses of Old Pro Golf, the Maryland beach resort's oldest and biggest miniature golf purveyor.

Mountain climbers have their Seven Summits Challenge -- bagging the highest peak on each continent. I had the Seven Courses Challenge.

I started my day on the course at 23rd Street, the central feature of which is a sort of Mayan/Aztec temple-cum-ziggurat. The course is accessorized with huge fiberglass dragons that are vaguely insectoid.

There is something quite wonderful about playing miniature golf by yourself. You're not held back by the slowest member of your group, the one who doesn't take it seriously. Yes, I had to endure the suspicious glances of other players, who wondered why a grown man was playing miniature golf by himself, but then, I'm used to people looking at me funny.

I shot a respectable six under and then trudged five blocks to the next course: Medieval Faire, where I bagged my first hole-in-one.

After playing the first of two courses at 68th Street, I sat down with Old Pro's general manager, Rick Schoellkopf, a boyish man of 47 who worked as an architect before succumbing to the inevitable and joining the family business.

Rick's father, Herb Schoellkopf, is sort of the Pete Dye of mini-golf: a course designer known for his strong vision. Herb, 84 and semi-retired, started out as a miniature golf contractor after World War II.

"He'd built 50 courses for other people before he realized that they made all the money," said Rick. So in 1950, Herb opened a course in Cherry Hill, N.J.

Herb is celebrated as a leading member of the so-called Philadelphia School of midget golf design: Each Old Pro course hews to a single theme and is dotted with moving hazards. Not the cliched windmills of so many miniature golf courses, but full-size human, or humanoid, figures: knights, cavemen, deep-sea divers, snake goddesses. . . .

The Schoellkopfs arrived in Ocean City in 1963 and haven't looked back. It's a family affair. Rick's brother Scott serves as facilities and maintenance manager. Other siblings have had various levels of involvement. "As soon as you could walk and hold a broom, you became an Old Pro employee," Rick said.

By the time he was a teenager, Rick was playing 15 rounds of mini-golf a day. He'd hustle the bartenders who stopped by after the bars shut down. "They couldn't believe a 14-year-old kid was taking their money."

The Schoellkopfs design the courses themselves, cutting hole layouts out of construction paper and fiddling with them: a loop-de-loop here, a bank shot there.

"We've learned things," Rick said. "Like you never have a hole with a ramp facing a window."

And they're partial to recycling. One of the knights holding a lance on the medieval-themed course at 28th Street appeared previously on a since-closed sports-themed course. Back then, he was Johnny Unitas throwing a football.

"We don't like things to go to waste," said Rick.

Ocean City real estate has become so valuable that you wonder how long the town's miniature golf courses can last. Indeed, Professor Hacker's Lost Treasure Golf, the one with the real airplane, soon will be replaced by condos or a hotel.

Rick says Old Pro isn't going anywhere. The employees are getting ready to battle it out this Saturday at the annual company tournament. There are cash prizes, and the top golfer will be awarded the traditional green warm-up jacket. Plus, anyone who can beat Rick's score gets a day off with pay.

It was time for me to play the dino-themed outdoor course at 68th Street. I asked Rick if he had any tips. He said the course had new carpet. New carpet meant the nap was standing up and the greens would be slow. I shouldn't be afraid to muscle the putter, he said. Then Rick quoted Chevy Chase in "Caddyshack": "Be the ball."

It was good advice. I birdied seven holes on the front nine, including a tricky bank shot under a brontosaurus on No. 8. I aced two on the back nine, including No. 13, a dogleg through a triceratops skeleton.

It was my last stellar round, though. I was wilting in the sun. The remaining courses were a blur of tiki heads, pole-mounted skulls, fiberglass alligators and screaming (non-fiberglass) children.

After nearly seven hours, 141 holes and 328 putts (including six holes-in-one and five double bogeys), I was nearly done: At the 19th hole on the pirate course at 136th Street, the hole that gobbles up your ball, I knocked my ball up a ramp and watched as it bounced off the side of an open treasure chest.

I was kind of glad it didn't go in. Getting it in the chest would have earned me a free game, and that was the last thing I wanted.

You Think You Could Do Better?

Here's what I shot. Par is 52, except where noted.

Temple of Dragons: -6

Medieval Faire: -16 (27 holes; par 79)

Undersea Adventure: -10

Dinosaurs!: -15

Polynesian Garden: -10

African Safari: -10

Pirate Ship: -2

My e-mail: kellyj@washpost.com