AC/DC warned us years ago that it's a long way to the top if you wanna rock 'n' roll. Fortunately for some of the fans who gathered at the band's May 22, 2010, show in Wels, Austria, it's a far quicker trip to the nearest emergency medical center.

The band, in town to promote 2008's Black Ice, set up shop at the local airport, where they were booked to perform on a runway. Heavy rains forced airport officials to arrange for the application of a layer of bark mulch in order to prevent damage to the waterlogged turf — which may have solved a potential landscaping problem, but ended up making the evening a painful ordeal for dozens of concertgoers.

Roughly 150 audience members suffered "severe allergic reactions" to the mulch. Their symptoms included burning sensations in their eyes and required immediate treatment. With a crowd of roughly 90,000 in attendance, the afflicted represented only a small minority, but for the show's promoters, it was just one more in a series of problems that had plagued efforts to bring AC/DC to Wels.

Weeks had passed before the band received final clearance to perform after a pair of WWII-era bombs were discovered on the site, as the Independent later noted, and local animal activists also attempted to prevent the concert on the grounds that it would disturb rare birds which had made their home in the area.

Medical drama aside, the show ultimately went off more or less without a hitch. Although the weather added some extra work for airport groundskeepers, it also made for a cool extra touch to the night's performance of "Thunderstruck" (embedded above), which was preceded by a burst of actual thunder.

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