Moving into a series with over one,000 episodes is daunting, but A single Piece is worth it. It is not regarded as the greatest anime of all time for practically nothing. One Piece features a lot of the most intricate, refined world-developing and best storytelling in anime.
2021 update: I have been about the fence about deleting this since it's so badly published, I used to be 17 at some time of producing rather than a native speaker, and my feeling this site on just one piece and anime on the whole has altered dramatically with the even worse.