A T-shirt bearing the slogan "Kennywoodn't'' arrived at my desk, the double-O being a bicycle's wheels.

It was easy to surmise what this was about. The 335-mile bicycle trail from Pittsburgh to Washington, D.C., won't be completed as planned this year largely because of an inability to pass through Sandcastle, the great water park in West Homestead owned by Kennywood Entertainment Co.

So I arranged to meet with Pete McAneny, president of Kennywood Entertainment and cycled out there. The trail on the south side of the Monongahela River is pretty great from Station Square (with one short detour), but the trail ends short of the Glenwood Bridge. From that point, if you don't know the terrain or aren't willing to carry or bounce your bicycle a couple of hundred yards along the CSX railroad tracks, getting to the other Sandcastle can be scarier than any ride at Kennywood.

After crossing and recrossing a tight and busy Carson Street, I wasn't surprised my bicycle had the rack outside Sandcastle to itself at 11 a.m. Wednesday.

Mr. McAneny says he has been wary of being put in this position for about a decade.

The trail "never should have come in this direction and should have gone across the river 10 years ago,'' he said.

Sandcastle is a long piece of property tucked between the river and the railroad, so parking can be tight. Mr. McAneny estimates that even a 10-foot trail through the site would strip him of 150 parking spaces.

Then there's the liability issue.

The Great Allegheny Passage is already a phenomenon among cyclists, with the little Trailside store and restaurant in West Newton, 33 miles southeast of Pittsburgh, reporting customers from 48 states and 13 foreign countries. It's only going to get more popular when the last nine miles -- all in Allegheny County -- are complete.

As with hikers on the Appalachian Trail, most cyclists would travel only slices of the ribbon, but some untold number of two-wheeled commandoes will want to do the whole shebang "justa saya didit.'' Combine cyclists with families driving or walking in Sandcastle and even a 15-mph collision can make a park owner with deep pockets nervous.

Trail planners "knew it and wouldn't listen and now they're on our front door trying to get people such as yourself to carry their water for them,'' he told me.

The last thing Linda McKenna Boxx, president of the Allegheny Trail Alliance, wants is to pick a fight with Kennywood. She put the kibosh on the "Kennwyoodn't'' campaign.

"We're all about helping everybody,'' she said. "We think the trail can only be an asset to Sandcastle.''

County Chief Executive Dan Onorato does, too. He has been out to eyeball the problems, among them the damage left by Hurricane Ivan in September 2004. That flooded the Streets Run culvert beneath the western parking lot, imploding the pavement and taking more than 100 spaces.

If the county can fix that and restore the parking there, "we can talk,'' Mr. McAneny said.

Kevin Evanto, spokesman for Mr. Onorato, said the county is trying hard to address Sandcastle's concerns. Repairing the Streets Run culvert would be part of multimillion-dollar project to mitigate flooding in West Homestead and the city's far southeast, and will require federal cooperation. Mr. Evanto could not say how the liability issue might be addressed.

Mon Valley gaps apart from Sandcastle are disappearing. Another four miles, including the old Riverton railroad bridge connecting McKeesport and Duquesne, should be complete this year, and trail planners say all but the Sandcastle piece look ready to open by May 2009.

When I returned to the Sandcastle bike rack Wednesday afternoon, two more bikes were beside mine. One belonged to the Rev. Douglas Boyd, assistant pastor of Good Shepherd in Braddock just up the Mon, who had been visiting parishioners who work at the park.

Father Doug, 58, was headed to the city, too, and he proved a good shepherd indeed, showing me that it's best to carry your bike for the couple of hundred yards on the river side of the railroad tracks to reach the finished trail into the city. Father Doug says I'd be surprised how many bikers do it. With a mountain bike, you might even ride the railside rocks, but my yard-sale racer wasn't up to that.

I did see a trio of cyclists quietly pedaling east through Sandcastle to The Waterfront, so it's hard to believe a win-win isn't possible here. This is a trail that has overcome the daunting 3,300-foot long Big Savage Tunnel in southern Somerset County, a dark, leaky, abandoned railroad tunnel that became a highlight of the trail -- though it took $12.5 million and more than two years to light it up.

Sandcastle could be a trail destination. Cyclists love water, entertainment and food, and while families loaded with beach stuff won't likely bike in, it's easy to envision teenagers and young urbanites pedaling up for a day in the water or a summer job.

This just won't be the summer that the full trail wheels out of the mind's eye.