The public can come aboard starting July 18, and Sound Transit is preparing for up to 100,000 riders that first day.

Out of the Downtown Seattle Transit Tunnel, onto the streets, under Beacon Hill, through Rainier Valley and onto Tukwila, the train glided.

Fourteen miles down, 14 miles back, not a hitch. Just some appropriate slowdowns for the stations along the $2.3 billion Sound Transit Link light-rail line, which got its first media inspection Wednesday.

The public can come aboard starting July 18, and Sound Transit is preparing for up to 100,000 riders that first day.

On Wednesday, John Helm, shown in the photo above, operated the two-car train, with Highway 518 traffic down below as he neared the Tukwila stop.

Seattle Mayor Greg Nickels played tour guide. Nickels is Sound Transit chairman, and for years — as confidence in the agency teetered, critics jabbed that buses would do the job cheaper, and taxpayers wondered if the trains would ever leave the station — Nickels insisted light rail was the future.

So with microphone in hand, standing at the front of the train, Nickels talked of revitalization in Southeast Seattle and pointed to where, on a less hazy day, riders would have a memorable view of Mount Rainier.

Not quite a whistle-stop tour, but a nice upbeat event for a mayor in the middle of a re-election campaign. “I’m very proud of this,” he said in an interview. “I’m busting.”