In the 1950s, the lines between what young mothers did and didn't do were pretty clear.

Did: Cook. Clean. Have babies.

Didn't: Run off in groups overnight, leaving husbands at home with the children. Swim naked in remote lakes at midnight. Stay up singing until the wee hours.

Still, a group of young mothers in the McMicken Heights area near Sea-Tac Airport had a question: "We just wondered why our husbands were off fishing, and we were home with the kids," said Rouha Rose, 75. "So we decided we'd go away for a weekend, too ... and nobody raised a big enough fuss to stop us."

Whatever they thought they were up to in 1955, the 11 women who went away for a single night in rustic cabins at Mount Rainier had no idea they were starting a tradition which would last more than half a century. Or that along the way, they'd form some of the strongest bonds of their lives.

They called themselves the "Lost Weekend Group," borrowing the title, but not the despair or depravity, of the 1945 Ray Milland movie. Their sisterhood spanned the terms of 10 U.S. presidents, countless economic ups and downs and vast cultural changes.

Says Margaret Gray, 78, the group's informal historian, "I think we women were practicing women's lib and didn't even know it."

The women loaded sleeping bags, watermelon, single-serving cereal boxes and other provisions into a few cars and set out for Ohanapecosh Campground on Mount Rainier's southeast flank, a bare two-hour drive from home.

"We thought, 'How dare we even consider leaving the kids with Dad?' " said Betty Isbell, 77, a late recruit for that 1955 trip. "But when you have a good friend across the street who says you need to get away, you just go ... I threw some undies and a nightshirt in a paper sack, and I went."

Out in the woods, "It was quite rugged," recalls Dorothy Jahn. "One of the women was supposed to make a fire and she broke the stove. It fell apart." Jahn, now 93, has been the eldest of the group, but kept quiet about her age because she wanted to fit in with the other moms, some nearly 20 years younger.

The joyful independence they exercised on that first trip included sitting as long as they dared in steaming hot mineral baths. They stayed up late, sang loudly, and at dawn one of them came face-to-face with a bear.

A sense of humor and a bit of daring have always been part of the Lost Weekends.

More than once in the early years, after dark, some would visit the nearest swimming hole "in the altogether," as Jahn politely puts it. Imagine their plight when one of their friends decided to point her car in their direction and turned the headlights on.

The "Lost Weekend" women originally came together several years before their first getaway, forming a co-op preschool where each mother worked one morning a week.

"When we were young, " said Rose. "We had no idea how to raise kids, no idea what the world was like. Somebody had paid our bills before and we expected somebody to keep on [paying] and for most of us, somebody did, thank God."

Though they enjoyed being homemakers and child-rearers, Rose remembers longing for something more.

"When I got married I went straight from my father telling me what time to be in, to a husband and then a baby so fast it made your head swim. And there was no time in between there when you made your own decisions. ... That was the main thing that's so special about this weekend. We made our own decisions. We went where we wanted to go."

As their children progressed into their teens, some of the mothers decided to resume their college educations.

Never mind that they weren't the youngest women on campus. When Delores Soelter, now 73, fretted that she wouldn't graduate until she was 40, Rose simply told her, "Well you're going to be 40 anyway, you might as well be educated."

About half became teachers or school administrators, drawing partly on their experience at the co-op school. Bette Van Gasken, the co-op's first teacher, went on to head the Head Start program in King County.

Despite busy schedules, the "Lost Weekends" remained precious and playful, like the trip to the blazing heat of Winthrop in 1976. "It was so hot we stayed in the pool and kept going to the store next door to buy more wine," said Gray. "I had taken belly dance lessons, and so we were in the pool trying to do belly dance lessons, loaded with wine."

The year 1978 brought a sad milestone. Joan Reel of Burien, mother of three sons, succumbed to cancer in her 50s. It was the group's first real loss. "She is still very close to our hearts," said Van Gasken, who was with Reel just hours before her death.

Reel was a talented artist and an educated woman who, among other things, taught her cohorts six different ways to fold napkins, depending on the nature of the event. "You never know when you may need to have a fancy napkin folded for a tea party," Van Gasken said.

"One of the traditions that we started then, at her funeral service, was all the Lost Weekend ladies went and we all wore our hats," said Van Gasken. "All women buy hats, but they don't wear them very often. So we just decided to all wear our hats to memorial services. It's crazy little things like that that keep us together."

Now that the women are in their retirement years, both words in their group's title are misnomers. They've switched from weekends to three- and four-night getaways during the week to get better room rates.

And if age has made them a bit less daring, at least a hint of rebellion is still lurking.

When one jokingly suggested they get tattoos as this year's gathering, June Yormark, 76, of Burien, obliged by hand-painting a butterfly or flower on each woman's ankle, advising them to keep them dry until they get home so their husbands would think they're tattoos.

Over time, the cast of characters has changed. Although several of the other early members have died and new women have been added, a strong core membership remains intact.

In fact, when they recently met at Fort Worden State Park at Port Townsend, four of the ladies present - Rose, Gray, Isbell and Jahn - were veterans of the 1955 journey to Ohanapecosh.

Among the missing was Betty Sheehan of Auburn, remembered as a "rascal" who had sometimes instigated the skinny-dipping sessions. She died in 1999, also of cancer. A half-dozen of the women have buried their husbands and, in recent years, even children, always counting on the support of one another.

"We used to see each other at weddings. Now we see each other at funerals," said Audrey Kirsop, 76, of Olympia. Kirsop had the distinction of being the only member to attend every "Lost Weekend" gathering, but had to let that string lapse this year to care for her seriously ill husband, Dick. "After 57 years together, you know where you need to be."

Says Isbell, "This group of friends has just stuck together through everything ... through life and death and birth and the whole thing ... I had a double mastectomy in 1985 and they all hung in there. The support is awesome."

And the tradition continues. Even before they left Port Townsend, the women were already discussing plans for next year's rendezvous at a retreat center in Southwest Washington.

Rose, perhaps the philosopher of the group, said aging and death haven't diminished their kinship. "Most of us are quite sure that [those who've died] are out scouting out places for Lost Weekend, for wherever we end up next. And that's a comfort."

In the meantime, they still enjoy what life has to offer.

"Getting old is a blast," said Rose. "You can dang well go where you want to go and do what you want to do. You talk it over with God, and if it's OK with him, I wouldn't want to be a husband that would try to stop us, that's for sure."