For art lovers, summer is the best time of year in Maine – and not just because the temperatures rise above freezing.

When the weather warms up, the state’s already thriving art scene kicks into overdrive, with a bevy of seasonal galleries ready to capture the attention of locals and tourists alike. Like any summer business, galleries come and go over time. But we’ve selected a few recent arrivals in our area that are likely to stay awhile.

Many of them are off the beaten path (and some are even open year-round). Of course, this list is not all-inclusive – even though reporting takes us all over the state, there’s no way of finding every new venue, but these selections share qualities that appealed to us and, we hope, our readers. We welcome your suggestions.

Most have serious curators with a clear vision of where they want their galleries to go. Some show fresh, innovative contemporary art, while others exhibit venerable paintings and sketches from the late 19th and early 20th centuries. And all are showing it in a way that sets them apart from the pack.

In other words, these are galleries that are worth the drive – even on a sunny day.

Adam Gallery, 140 Battle Ave., Castine, open weekends and by appointment, 326-8272.

In the fall of 1999, painters Joshua and Susan Adam left northern California for Castine, where Susan spent her childhood summers. The pair met at Colorado College, where both majored in art, and moved to a small town in Humboldt County, Calif., an inland town that is much more remote than Castine.

“This is like uptown living,” Joshua Adam said.

“This is like New York,” Susan added, laughing.

The move has served the couple well. Joshua works in the plein-aire tradition, and has found the crisp, stark winters inspiring, even if his oil paints start to freeze after 20 minutes. For Susan, who often does commissioned portraits, Castine’s rocky beaches reignited her love for landscape painting.

“I couldn’t paint landscapes in California,” she said. “I’m really drawn to the coast.”

Because of town ordinances, the Adams can only show their own work, in a renovated, heated carriage house on their property. Though they have shown their work in other galleries, having a space of their own has its benefits.

“The galleries around here are so full, we’d have two paintings on the wall,” Susan Adam said. “Here, we can have 30.”

Artistree Gallery, 134 West Main St., Fort Kent

The 2004 Biathalon World Cup galvanized a group of northern Maine artists to band together to form an artists’ cooperative. The result is Artistree, a much-anticipated new gallery in downtown Fort Kent.

Though the work is for sale, the focus is more on bringing the experience of art to the community, especially local schoolchildren. The gallery is staffed by working artists, who are available to discuss their work. And while the art is inspiring to the public, the interaction is equally inspiring to the artists.

“I’m excited about the opportunity to be part of this gallery because it moves me,” artist Doug Clapp said. “It gives me great motivation to continue doing great artwork.”

In addition, it gives the artists a chance to branch out. Gallery director Jerry Jalbert, a professional portrait photographer, is able to share his passion for nature and the environment through Artistree.

“It’s completely unrelated to what I do in daily life,” he said. “This is the stuff that feeds my soul.”

Clark Point Gallery, 46 Clark Point Road, Southwest Harbor, 244-0920, www.clarkpointgallery.com

Though he spends much of the year in Philadelphia, Peter Rudolph’s ties to Maine go way back. While earning his master’s degree at the University of Pennsylvania, he studied under Neil Welliver and Alex Katz, and he’s summered on Mount Desert Island for years.

At his Pennsylvania venue, McClees Gallery, he restores, conserves and sells old paintings. And he kept finding more and more from Maine.

“I buy them just because I love them,” he said. “I figured, I’m running into so much art from Maine all over the place, I might as well open a gallery in Maine.”

So Rudolph and his wife, Ingrid, opened Clark Point Gallery last summer in a renovated old Cape. They have since turned it into a destination for Maine art from the late 19th and early 20th centuries, including historically important paintings of Ogunquit, Monhegan, Mount Desert Island and the Cranberry Isles.

“These painters are a who’s-who of American art,” said gallery assistant Clara Baker. “But different pieces are significant to different people.”

Among the highlights are an extensive collection of sketches by Xanthus Smith, as well as paintings by Phillip Little and Andrew Winter.

Coppershed Gallery, 288 Vaughn’s Neck Road, Warren, 273-2784.

Guy Hughes’ vision sprung, in part, from frustration. The English teacher-turned-sculptor had been summering on a farm in Warren for nearly 30 years. He had a studio in Maine and a studio in Boston, where he lives in the winter, but he didn’t see much similar work.

“I was someone who likes sculpture a lot, and there’s very little sculpture in galleries around here,” he said.

Make that abstract sculpture. And abstract art. Even though the state has a strong tradition of artists who have boldly worked in abstraction, representational painting has a stronger foothold here. His quest for a venue made him a pioneer in Warren – when Coppershed Gallery opened last week, it became the first multi-artist gallery in the town’s history.

In a soaring space attached to his Cape, he shows his own sculpture in bronze, copper and steel, along with work by sculptors Julie Levesque, John Bisbe, Megan Cronin, Maggie Stark and Deb Todd-Wheeler. The gallery also features paintings by Jim Kinnealey, Cynthia Hyde, Vivien Russe, Jennifer Mumford and Deborah Winship.

Isalos Gallery, Main Street, Stonington, 367-2700, www.isalosart.com

In Maine, there are dozens, perhaps hundreds, of places to see landscapes and seascapes. And, on the surface, Isalos appears to be one of them. But Michael and Rebecca Daugherty’s goal is to show Maine in a different light.

“All along, I’ve wanted to have some diversity,” Michael Daugherty said of the gallery, which is in its second season. “I’m most interested in fairly contemporary-looking work – things that I haven’t seen before, which makes it challenging for landscapes.”

He’s met the challenge. He and his wife opened the gallery in part because Rebecca is a painter, but they’ve assembled a roster of artists who share – not parrot – their vision. Among the highlights are Kitty van der Meer’s vibrant oils, Emily Brown’s soothing, almost abstract works in ink on paper, and the intricate paintings of Vaino Kola, whose work was featured in Carl Little’s book “The Art of Maine in Winter.” He’ll have a solo show in August that features his paintings, pastels and etchings.

Lake Hebron Artisans, 8 Greenville Road (Route 15), Monson, 997-3731

The most innovative gallery concept prize goes to Lake Hebron Artisans, whose storefront exhibitions are on view 24 hours a day, seven days a week.

More than mere window dressing, these are real – and provocative – art exhibits. The thought-provoking Middle Ground exhibit, whose installation titled “Are You an Average … ?” encouraged passers-by to interact with the piece through surveys and open-ended questions, received a Maine Arts Commission and Maine Humanities Council grant last fall.

A “General Store” exhibit, which centered on Monson photographer Berenice Abbott’s work, transformed the window into an old-fashioned store that happened to have a gallery. The current exhibition of work by Seth Steward, a turn-of-the-century painter, includes landscapes, portraiture and a genre painting, as well as a family scrapbook. The show is on view through Aug. 1.

Northeast Fine Art and Design, Main Street, Northeast Harbor, 276-9890

Leslie Rindler had no idea what to expect when she took over the former A.J. Bueche Fine Art space in this summer haven.

“It just seemed like fun,” Rindler said.

She knew one thing: she wanted art and furniture, and both share the spotlight. While rotating exhibits adorn the walls – John Almard LeBlanc’s whimsical pastels and Richard Kapral’s textural, glossy oils are currently on view – tables, chests and chairs by some of Maine’s master craftsmen take the floor.

“It offsets the paintings,” Rindler said. “Then people can see it all together.”

What Rindler lacked in gallery experience, she makes up for in taste – every corner of the gallery is full of compelling work, and each discovery is more intriguing than the next.

William Ryan Gallery, 108 Main St., Belfast, 338-9252, www.williamryanfinearts.com

William Ryan, most recently of the National Theater Workshop of the Handicapped Gallery, has opened his own venue right up the street. In addition to featuring regional favorites such as NTWH instructor Kirk Moore, Ryan also shows work by nationally known artists such as Chuck Close and Red Grooms.

Many of the artists have ties to NTWH, including Close and James Strickland, whose recent work includes delicate kites that incorporate his love for painting and sculpture. The gallery also shows work by Kate Fitzgerald, Carl Fowler, Maureen Stalla, Donald Traver, Matthew Lecher, Cig Harvey, Ted Keller, Steve Kennedy and David Vickery.