@SaiyaJedi:
I became a fan back in 2003, when the English version started running in the North American (print) Shonen Jump. Like most people, I followed along with mild interest until the Arlong story arc, after which point I was hooked. Don't remember exactly when I first started following chapters as they were released in Japan (as that was much harder back then than it is now), but my first current release volume of the series that I picked up was Volume 32 in early 2004. Most likely, I probably got into the weekly scene right after the Davy Back fight but prior to the start of Water Seven (so, around chapter 320-321 in May 2004). I do have a vague recollection of seeing Aokiji freeze Robin, so that's my best guess. I followed the entire Water Seven / CP9 / Rocketman / Enies Lobby storyline from beginning to end as it was happening in Japan, and also studied in Kyoto for a few months during that time.
Anyhow, after really getting into the fandom in the first half of 2004, I very quickly got caught up as much as I could through various sources of varying quality (though I've since gone back and re-read the series legally and in Japanese), and was following along with the Japanese version and knew what was going on by the beginning of 2005 or so. Don't follow it every week in Jump like I used to, but I still buy the collected volumes and spot-check the magazine when I pick it up for other thingsJumpVictoryCarnival'14entryslip. I also watch it on TV, mostly by dint of it being on after Dragon Ball Kai. (Luckily, the pace of the anime is so excruciatingly slow these days that I didn't miss too much in the three years Kai was off the air.)
I've also seen Strong World, Z, Episode of Chopper Plus, and Goro Inagaki's Voice-Acting Is Even Worse Than His Singing, in theaters.
Still waiting for Wanokuni and Elbaf after all these years.
That's a rather storied duration as a One Piece fan, outstanding.
Well, Robin is frozen in 320 rather than 321, so let's go for that.
Chapter 320, "Greatest Power", released on the 10th of May, 2004.
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@bobop:
I think it was when luffy used Coc on Duval's bull.
Google search… So Chapter 495 it seems.
Indeed it is.
Chapter 495, "Gaon Cannon", released on the 7th of April, 2008.
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@Steel:
Chapter 617 Zoro cut Hordy
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I was wrong 618 not 617
Second time lucky.
That's Chapter 618, "Proposal", released on the 19th of March, 2011.