You’d think that after the enormous success of the first three folk festivals in Bangor, we’d be over that sense of giddy disbelief by the time the fourth one rolled around.

Yet as we longtime residents strolled through the crowds during the past weekend’s American Folk Festival, the seasonal transformation of our humble little city and its beautifully restored riverfront park seemed nearly as magical as it had when the first National Folk Festival pitched its tents in Bangor in 2002. We could hardly recognize the old place back then, and the extraordinarily vibrant look and feel of this latest celebration still had the power to make many of us do a double-take.

We haven’t forgotten, after all, that an event of this magnitude could never have happened in Bangor several years ago. We were not nearly ready as a community to believe we could actually pull off such a large-scale shindig, nor did we have a suitable site on which to stage one.

The changes on both counts have been remarkable, even if the thousands of jubilant out-of-towners who wandered the festival grounds over the weekend could never appreciate what it took for us to put together such a spectacle.

Back in the early 1980s, few Bangor residents could even have imagined the lovely riverfront that exists in town today, let alone the economic benefits that such an attraction could bring. They had long before turned their backs on the Penobscot River, and the derelict, inhospitable and oil-soaked stretch of real estate that ran alongside it. In his 1983 book “Rivers of Fortune,” the Maine nautical writer Bill Caldwell offered a grim picture of the city’s neglected waterfront at the time.

“We came in February by Coast Guard icebreaker, 24 miles up the Bangor river,” he wrote, “and the only half-safe place to tie a boat was to a decrepit piling beside a garbage-strewn, abandoned coal yard.” The waterfront, he continued, “is a sad, sleazy, deserted slum of what is left of the port of Bangor, which once boasted the busiest lumber port in all the world.”

A bleak assessment, to be sure, and a fair description of what the city was up against when it began investigating what that forlorn strip of land might represent one day, cleansed of its grimy industrial clutter of oil tanks and toxic earth. In 1986, the city began buying up available riverfront properties and extending the project’s scope from six acres to 36. By 1990, a once-hazy vision for the area grew more focused when Maine Central Railroad relocated its train-switching operation from the site. And even as the more grandiose plans for the nascent waterfront came and went – anyone remember the 200-room Marriott Hotel that never got built down there? – the countless critical though subtle improvements made to the area over the years eventually allowed the city’s residents to see possibilities we never could have conceived in the past.

Yet even as we slowly came to sense the potential in our former eyesore, it took the folk festival to finally make it real, to change how we envisioned the emerging economic health and cultural vitality of the city.

To many of the hundreds of thousands of visitors we’ve hosted since 2002, the festivals may simply have been enjoyable three-day stops on their busy vacation schedules. But for those of us who live here, who know how very far we’ve come as a community, the good feelings should never fade when the summer ends.