We can't say for sure the last time we heard 'La Grange,' ZZ Top's ubiquitous musical calling card. But if it wasn't today, it was probably yesterday, and it could have reached us from a hundred different sources.

It may be hard to believe, listening to the radio today, but there was a time when ZZ Top had trouble even getting noticed.

It certainly wasn't due to a lack of talent -- the trio had the attention of their peers right from the start, with Jimi Hendrix naming frontman Billy Gibbons "America's best young guitarist" early in their career.

However, despite releasing two extremely solid albums -- including 1972's 'Rio Grande Mud,' which just turned 40 --  and developing a reputation as a powerful live band, large-scale success eluded the group until 'La Grange' knocked down the door in 1973. The song nearly hit the Top 40 and propelled their third album, 'Tres Hombres,' to the top reaches of the album charts.

A loving lyrical tribute to Texas's favorite little whorehouse, the track found the band enhancing a souped-up but otherwise highly traditional blues boogie with their own distinctive twists and turns.

Part of what's made ZZ Top so special over the years has been their ability to expand, mutate and transcend the blues genre on songs such as 'Cheap Sunglasses' and 'Sharp Dressed Man.' But 'La Grange' shows them connecting to their original inspirations in extremely pure and undeniably appealing form.

Gibbons didn't need any trickery to work his magic on this track, telling Guitar World about the song's recording: “That is straight guitar into amp: a 1955 Strat with a stop tailpiece through a 1969 Marshall Super Lead 100. That fuzz sound in the lead and in the front and back end of the composition is just pure tube distortion."

If you need another reason to justify 'La Grange''s placement on our Top 100 Classic Rock Songs list, simply go to the movies, turn on your radio or watch television for a few hours. Odds are you'll hear the track setting the mood for at least one film, TV show, commercial or video game before too long.

It's a testament to both the song's immediate appeal and enduring quality that despite all this airplay and multi-media placement, it's still a thrill every time Gibbons launches into his deep growl for that famous intro: "Rumour spreadin' a-'round in that Texas town / 'Bout that shack outside La Grange..."

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Watch ZZ Top Perform 'La Grange'

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