WEST LIBERTY, Ohio — Tourism traffic to the historical Piatt Castles — picturesque stone Civil War-era homes that hug the western Ohio hillsides — has been steadily falling for 10 years.

But Margaret Piatt hopes to save the attraction by joining forces with a restored theater, a Frank Lloyd Wright house and other nearby tourism sites, creating a travel corridor tied to a scenic highway.

Rising fuel prices and increasing competition for the entertainment dollar are putting pressure on tiny, one-stop tourist sites. So states and regions are starting to pitch their tourist attractions as a package, hoping that more is better.

New Hampshire has begun offering multisite Golden Pond and Robert Frost tours. Mississippi is starting a blues heritage trail. And a group in northeast Mississippi wants to package sites associated with novelist William Faulkner.

"When they pool their resources they can have a major-league Web site and they can be competitive," said Allen Kay, spokesman for the Travel Industry Association of America.

Similar efforts are being made in many big cities, where discount passes and cards are being used to entice tourists to a variety of attractions.

The two Civil-War era Piatt Castles were built at a time when Americans were fascinated with castle-like architecture. Constructed of limestone from nearby quarries, they feature soaring gables, ornate frescoed ceilings, Gothic arched walls and parquet floors. They stood in stark contrast to nearby farmhouses and came to be called castles by the locals.

The castles were built by Donn and Abram Piatt, journalists and officers in the Union army, on a pastoral site where a Shawnee Indian village stood in the mid-18th century.

Last year, the castles had 15,000 visitors. "We're sort of invisible," said Margaret Piatt, Abram Piatt's great-great-granddaughter. "I mean, where are we? We're in the middle of nowhere. But that's just what people like about us."

Enter Excursion 68, a plan to promote the tourist sites along a 50-mile stretch of U.S. 68 as a single attraction for travelers interested in architecture and the arts. The sites include the Piatt Castles, the Holland Theater in Bellefontaine, Wright's Westcott House in Springfield, and the artisans and shops of Yellow Springs, a throwback to the 1960s where tank tops, sandals and T-shirts emblazoned with the likes of Bob Dylan are common attire. A Web site promoting Excursion 68 is to be started this summer.

Also in the works is the Mississippi Blues Heritage Trail, marking significant sites in the history of blues music. The first 10 sites on a 100-mile stretch are expected to have markers by the end of the summer. They include a radio station in Greenwood where B.B. King first performed professionally, the grave of singer Charley Patton near Indianola, and the Riverside Hotel in Clarksdale, where Muddy Waters, John Lee Hooker and Sam Cooke stayed, and where Bessie Smith died when the building was a hospital.

The goal is to educate residents about their heritage, inform travelers and attract "blues pilgrims," tourists lured by the history of great blues artists, said Luther Brown, director of the Delta Center for Culture and Learning at Delta State University.

"We hope we see an increase in tourism, and consequently, an increase in support for local business ventures," Brown said.

Collective marketing worked for Montana, which went to the regional approach in 1986 with Custer Country, a corridor that includes the Little Bighorn battlefield, a portion of the Lewis & Clark trail, dinosaur digs and a wild-horse range.

The number of tourists who go to Montana has increased from 2.5 million in 1986 to 10 million last year, with Custer Country drawing one of every four. Annual spending by tourists has increased from about $150 million to $2 billion.

"We had so many small towns in eastern Montana that didn't have the ability to market themselves," said Jim Schaefer, executive director of the Custer Country Tourism Region. "They just had to go digging and scratching to find funds."