When you’re in Muenster, you have to go to the path, people said. It goes through a park, across a street, and continues through a golden wheat field over a picturesque footbridge. That’s the art.

Pawel Althamer was the artist, and his Path was one of 33 sculptures scattered around the German city this summer during Muenster Sculpture Projects 2007. This was my first time seeing the once-in-a-decade public art show, and after renting a bike, I found Path on the map, with a notation: “Between the western shore of Lake Aa and Haus Bakenfeld.”

But the path did not begin on the western shore of the lake. It was hard to figure out where it did begin. I stopped at an intersection where two walking paths streaked off the paved bicycle lane, and chose one. It led to a crater.

I walked to the top of the crater, looked down into the glowing, gaping hole, and saw a full-scale imitation Romanesque church spire sitting in the hole with a shovel next to it.

This was not the path. It was Guillaume Bijl’s Archaeological Site (A Sorry Installation), a plaque informed me. The plaque claimed to be the marker for the archaeological dig that turned up this so-called relic.

This is the sort of thing that happens at Muenster Sculpture Projects, I began to realize. The art is out there in the world, all over the place in the city, so it’s exhilaratingly difficult to tell what is world and what is art, or in this case, where the art is exactly. For the 107-day duration of the exhibition, the whole city becomes a revolutionary experiment in redefining public art. (There has been talk of Muenster not continuing after this year. That would be terrible. The combination of joy, intelligence, and, increasingly as the show goes on, history, in MSP is unmatched.)

One artist, Mark Wallinger, tied a three-mile perimeter of fishing line above the city, but it was only a fantasy to me: In several hours of biking around the city, I never caught a glimpse of it. I also didn’t catch Gustav Metzger’s small, unassuming heap of granite stones, which were moved to a new location in the city every day.

Here’s what I didn’t see (you have to squint to catch the fishing line on the left side of the image):

On the edge of the lake, Tue Greenfort’s silver liquid manure truck spouting cleansing agents into the lake looked like a municipal vehicle just doing its thing, not an art project.

The art in Muenster is loose, relaxed. I started to be aware that it was playing, happily, with its own credibility.

Still determined to get to Path, I biked back to the intersection and took the other route. At the two-lane road, I got off my bike, crossed it, and entered the field, walking the bike.

The sun had come back after a flash rainstorm, and the soil was thick and frosting-moist. I followed other people’s footsteps.

About 30 feet in, the footsteps ended.

In pictures I’d seen, the single-file path was shaved out of wheat. You easily could see where to go.

But without wheat, you were lost. “Between the western shore of Lake Aa and Haus Bakenfeld,” the map said. Across the field, maybe two soccer fields away, was a white house with a perfect A roof.

Haus Bakenfeld. It had to be.

I walked the bike that way. On one side of the field was a stand of pine trees, on the other a row of houses with their backs to me. A teenager ran out into the muddy field to grab a ball and glanced at me.

Did he know about the path?

I started to sweat.

Was there a path anymore?

I could see into some of the houses. They weren’t modest and old-fashioned, like the one I was headed toward. These were made of glass and had big, tidy Germanic gardens separated by hedges. A woman in a backyard played with a baby. Occasionally I laughed out loud. It was entirely possible that Haus Bakenfeld was not the one I was walking toward, and that my belief in art was making me ridiculous. I was in the middle of a muddy field, jetlagged, sweating, sunburning, and bleeding from a blister, and I couldn’t find the art.

At the last house before the white A-roof, I caught the eye of an old woman holding a ladder while an old man up on it was reaching for a pear on a tree. I asked for Haus Bakenfeld. I pointed to the house in front of me. They shook their heads. I asked whether anybody named the Bakenfelds lived around here. They smiled gently, as at an addled person. “The people who live there are Peter and Kristin Klimke,” the man said in German, spelling the names.

He pointed behind me, all the way back across the field, across the road with its tree-lined sidewalks, and into the park where I’d come from, and said, “The art is over there.”

Back over there, again at the intersection where I started, a group of people had gathered. They looked at their maps and pointed in various directions, debating. When they saw me coming back along the path, they stopped me. “Is that the path?” they asked. I told them yes, considering that they’d be following my footsteps, not the artist’s. I told myself that the artist would approve, because Muenster during the Sculpture Projects is that kind of place.