Sundown was an hour away, but already it was hard to find a place on the grassy knoll above the river. Middle-aged couples, parents maneuvering strollers down a wide stairway, young lovers and teens traveling in packs staked out their ground and waited for the summer's biggest event to begin.

Fireworks? In a fashion.

I was in Providence, R.I., for WaterFire, which proves that even if you think you've seen everything, you haven't.

Finally, darkness fell, the air cooled and fire-tenders in slow-moving boats carefully lit 80 bonfires, hovering just above the Providence River, to wild applause.

"It's a good idea," said a smartly dressed woman, leaning against a brick wall. "How else would you get people to Providence?"

Before visiting Rhode Island's capital, I also had my doubts. Providence was a quick stop on my way to the real vacation: trendy Newport, posh Cape Cod, and uber-quaint Martha's Vineyard, on July 4th, no less!

Sorry, Providence. Who knew you'd offer the most memorable adventures -- culinary, intellectual and aesthetic?

From the Rhode Island School of Design (RISD) to the Providence Athenaeum with its creaky floorboards and leathery smell (and is that Goethe in the card catalog?) to old-world Federal Hill, where we ate divine scallops and eggplant, Martha could wait.

No wonder the Daily Telegraph of Great Britain in 2011 proclaimed Providence "New England's coolest city."

Hottest, too.

WaterFire is part circus act, part street fair, and one of the country's most remarkable open-air art installations. Bonfires emitting an oaky aroma flicker hypnotically along the nearly milelong stretch of water, while piped-in music (opera to classical to pop) follows visitors as they stroll and snap photos with their cellphones.

Some families packed picnics, but food carts and drink stands are abundant, offering average to excellent food. I made a beeline for French pastries (after pondering Indian curry and instead eating a healthful chicken sandwich). Twenty or so hip and trendy restaurants near the river's banks add to the allure and ambience.

"It's something different, really romantic," said Mary Hotz of Boston, attending WaterFire for the fourth time. She got smart this year and wore flip-flops instead of high heels.

A radical history

Providence always has prided itself on being different. The city was founded in 1636 by Roger Williams, after he was booted from the Massachusetts Bay Colony. His crime? Radical thinking, if you consider the separation of church and state a radical idea. That dedication to religious freedom endures. Providence houses the first Baptist Church in America. The country's oldest Quaker meeting house and oldest synagogue are located in Newport, 30 minutes away. The city celebrates cultural diversity, too, with thriving Italian, Jewish, Portuguese and Irish neighborhoods.

From Providence, you can drive to Boston in under an hour and to Cape Cod in two. But when you go, plan to spend at least two days in this special former mill town. I easily filled up two days, traveling with my boyfriend, Patrick, who grew up there.

One of our first forays was into RISD's Museum of Art, which featured an enticing exhibit called "Cocktail Culture." Little black dresses, purses, shoes, handbags, jewelry, even magazines and matchbooks ... history never looked so sharp.

Patrick, though, was antsy to show me the nearby library and, after two hours of Coco and Christian Dior, I owed him one.

Turns out the Athenaeum was a trip highlight for me, too.

The three-level Athenaeum, which opened in 1838, houses more than 150,000 books, periodicals, DVDs, even medieval manuscripts. The library's floorboards are original and uneven. The stairs are narrow. Everything creaks. The smell is leathery, the light ethereal, thanks to a frosted glass ceiling. It was wonderful. We spent most of our time perusing old-fashioned card catalogs with wooden index cards, some handwritten, others typed using the Dewey Decimal System. (Yep, that was Goethe.)

Built on seven hills

Back outside, I learned a bit about the city's structure. Providence, like Rome, is built on seven hills. The three most famous are Federal Hill (the Italian section where we inhaled those scallops served by a waitress who took our "ordah" and offered us "waddah"), College Hill (with Brown University and RISD) and Smith Hill, where the State Capitol overlooks the reclaimed and bustling downtown.

A drive through the city's winding, intimate neighborhoods is a must, with homes dating to the 1700s. Benefit Street, in particular, features home after home on the National Registry, including John Brown's house.

We also drove through lush Swan Point cemetery, located on the Seekonk River. The contemplative drive offers beautiful headstones everywhere you look, carved with austere names (Adams, Lincoln, Hamilton) resting under stately oaks and elms.

Equally stately, or a complete eyesore depending on your point of view, is another landmark: The city's 200-foot-high railroad lift bridge, permanently stuck in its raised and rusted position. A certain kid used to jump off that bridge, which is easily spotted from an airplane. I loved it. Urban decay at its most attractive.

Each night, we headed into the new downtown artists' quarter to walk, shop and listen to jazz.

And while Federal Hill, with its welcoming pineapple-logo entrance, offers renowned Italian cuisine, Patrick found his way before we left to another culinary favorite: Dunkin' Donuts, founded in nearby Quincy, Mass.

As a boy, Patrick remembers his dad returning home every Sunday morning with the daily newspaper and a box with a dozen of the sugary treats. He remembers, too, the bakery's motto: "It's worth the trip."

The same can be said for Providence.

Gail Rosenblum • 612-673-7350