The “Route 66 Adventure Handbook” is a guidebook for travelers who aren’t in a hurry.

And that should probably be you.

Author Drew Knowles has just released the fifth edition of his handbook (Santa Monica Press) about the highway that author John Steinbeck famously nicknamed “the Mother Road” in his novel “The Grapes of Wrath.”

The highway has been officially decommissioned for decades, long supplanted by speedy but soulless interstates. Knowles, however, has sleuthed out the old route and the dozens of offbeat attractions, vintage motels, restaurants and souvenir shops still to be found along the way.

Route 66 has long had a hold on the public imagination, perhaps because of Steinbeck, or maybe because of the 1960s television show “Route 66.”

The song “(Get Your Kicks On) Route 66,” written in the ’40s and covered by dozens of musicians since, long ago embedded the highway, and its route, in my consciousness.

“It winds from Chicago to LA, more than 2,000 miles all the way …”

“There’s certainly a geography lesson in that song that sticks in your head,” said Knowles from his home in Little Rock, Arkansas.

Knowles first fell in love with the Mother Road in Tucumcari, New Mexico, at an old souvenir stand shaped like a teepee and a restaurant wearing a huge sombrero.

“That’s where I first saw those kitschy buildings associated with Route 66 that I had thought were long gone,” he said.

After that, Knowles and his wife would visit stretches of the old highway on vacation, a week at a time, discovering and documenting more of the old Route 66 tourist sites, some still operating, some in ruins.

“I had also caught the photography bug, and 66 gave me something to photograph,” he said. “I also did a lot of note-taking and learning as I went. At some point I had accumulated so much information I thought I should share it in a book.”

Taking time to seek out the old route and the sights to be seen there can be a rewarding way to travel, Knowles said.

“When I get out on the highway, I want to sample the local color and eat the local cuisine and all of that,” he said.

“Interstates have bought us some time, getting from point A to point B. But whether you have on your AC or your heater, on the interstate your windows are always rolled up. You don’t hear the church bells ringing and you don’t smell the new-mown hay like you used to.”

-- Steve Stephens can be reached at ssstephens@dispatch.com or on Twitter @SteveStephens.