This weekend, you can tour the country without having to go any farther than the grounds of Wolf Trap, which is hosting the 44th National Folk Festival. One ticket will get you:

* Mountain music that seems entirely at home in the slightly rolling hills of north Virginia.

* Ethnic music born and bred on the shores of Sicily, Cambodia, Spain and Mexico before finding homes in San Francisco, Washington, Albuquerque and elsewhere.

* Gut-wrenching songs floating through that very thin curtain of hope and despair that separates blues and gospel.

What you can hear through tomorrow afternoon are instruments that share the same strings, but different actions, and tunes that are deeply felt whether they reflect religious conviction, the dynamics of hard living or the exuberance and release of party music.

For instance, you can hear Henry Townsend recall an earlier era, when the Depression was called a depression and he and other St. Louis bluesmen played rent parties so people wouldn't lose their homes. His wife came up and sang an "undiluted" version of St. Louis Jimmy's " 'Goin' Down Slow' 'cause I feel it's something each of us is doing each and every day." There wasn't any noticeable disagreement, but then blues have seldom left themselves open to contradiction.

You can't get much more real than Doc and Lucy Barnes and the Rev. Nathaniel and Sister Fleta Mitchell, all from Athens, Ga., and with more than 280 years of living by the Good Book among them. They stood strong in their faith, singing old-fashioned gospel songs such as "You Better Mind What You Say."

There's a wealth of church music at Wolf Trap: Birmingham, Ala.'s, Four Eagle Gospel Singers sustain the black-quartet tradition that thrived in the '30s and '40s before eventually moving to the street corner and helping birth rhythm and blues.

The Dean Family Full Gospel Quartet from Morristown, Tenn., accents the more staid white tradition in gospel but has a singer, Dolores Dean Carter, with one of the most gorgeous country voices imaginable. The two groups shared an afternoon harmony workshop and watched each other with obvious respect. Elder George Dean looked out over the crowd at one point and said, "I see a lot of wonderful faces here today. There's a meeting on the other side of life and I believe I'll see a lot of you there."

There are myriad flavors of the folk experience available for inspection at Wolf Trap, from James Kimbrough's classic country to the Spanish graces of Lorenzo and Roberto Martinez to the wild Appalachian rhythms of the Roan Mountain Hilltoppers with Bill Birchfield's upside-down, left-handed guitar played over the top of the neck. Like everything else, it works.

One particular tradition is always evident at the National Folk Festival: family. There's Gordon Tanner and the Jr. Skillet Lickers whose old-timey music goes back to the original Skillet Lickers in the '20s and whose future seems secure in a fourth-generation fiddler, Russ. The Hilltoppers' Creed and Joe Birchfield are 70 and 76, respectively, with a guitar-playing son and washtub-bassist daughter-in-law. Otha and Stanley Emert are brothers; fiddler Junior Daugherty performs with daughter Tammi; guitarist Denzil Wine backs his fiddling father, Melvin. Everywhere you listen, it's family and faith.

But it's more than family that creates a bond at Wolf Trap. It's a roots simplicity that can make anyone feel down-home, a warmth that baptizes. Almost all the performers are carriers of traditions learned from family, solidified by environment and most certainly safe from commercialization. Yet they celebrate the vitality, beauty, dignity and strength of those traditions with rare dedication and enthusiasm. Few of these wonderful musicians and singers are pros, but they're all poets.

The National Folk Festival continues today and tomorrow with afternoon mini-concerts and workshops and a concert this evening.