The “Jersey Shore” gang in Italy. (Ian Spanier Photography)

All good things must end — even “Jersey Shore” which, MTV announced Thursday, will fold up shop at the end of its upcoming sixth season. The show that saved MTV will premiere its sixth and final season on Oct. 4.

“Jersey Shore” is another of those tragic TV industry stories. Unveiled to an unsuspecting public in December of 2009, The Situation, Snooki, and the rest of the gang still had so many neighborhoods to terrorize, so much binge-drinking, hooking up, and emotionally fraught fighting to accomplish.

But some of the stars had become distracted with their own spin-off starring vehicles, and MTV decided to pull the plug before “Jersey Shore’s” ratings got any lower and costs got any higher.

The show’s headliners are reportedly making more than $2 million each for the sixth season, which works out to about the same paycheck per episodes as the adults on “Modern Family” will get for that show’s upcoming season. The rest of the “Jersey Shore” cast make approximately what the kids on the ABC hit comedy are slated to make this coming season.

But “Jersey Shore’s” ratings have slipped noticeably since the heady days when it hit 8.8 million viewers at the start of its fourth season – an MTV record. MTV tried to broaden out the show, sending the gang to terrorize Florence, Italy for that fourth season. But the cast clearly hated playing fish out of water, the locals weren’t impressed, and viewers began tuning out.

Returning to Jersey for Season 5 didn’t help revive the ratings, and by that season’s penultimate episode the show’s ratings were back down to first-season levels. “Jersey Shore” continues to be cable’s No. 1 ranked series among 12-34 year olds, but here too, the ratings have takena big hit.

Besides, “Jersey Shore’s” happy hedonistic days are behind it, what with Mike ”The Situation” Sorrentino now living with a sober coach and giving interviews to MTV’s Sway about the “rainy days” he’s had since struggling in rehab with his addiction to “prescription drugs,” and Snooki now a mom. Where’s the fun in all that?

Thursday’s announcement marks The End of an Era, MTV said modestly.

The news was unveiled Thursday to give fans time to grieve, and clear their schedules for a mess of “Jersey Shore” send-off programming, starting almost immediately after the holiday weekend.

On Sept. 6, MTV will celebrate “Jersey Shore” all day long, until it takes a break to telecast the “2012 Video Music Awards.”

At 11 a.m. that day, MTV will run a “Jersey Shore” marathon, featuring past episodes that should have, but did not, win awards, for Best Bromance and the like. That’ll be followed by a retrospective show, “Gym, Tanning, Look Back,” at 6, in which cast members reminisce like middle-aged folk at their high school reunion.

At 7, the gang gathers for their first live interviews since MTV announced their show was kaput, from the “VMA’s” pre-show red carpet. The network threatened other things also were in store, including an after-show each week during Season 6, a “scintillating reunion special,” etc.

Though the show will be gone after this coming season, it will live on in spin-offs. “Snooki & Jwoww,” which wraps its first season on Sept. 13, has already been renewed for a second season. But don’t hold your breath on “The Pauly D Project” which had a lousy opening.