Started in 1997 and still running. Follows Monkey D. Luffy and his crew as they sail the Grand Line looking for the treasure of the title. I am up to Elbaf. Long is an understatement.
Marineford is the arc I keep coming back to. Not for Ace — for Blackbeard. You watch his crew arrive as nobodies and leave as a real power, and the whole balance of the world shifts inside one arc. Very few shows manage that.
One thing the anime got right: there is barely any filler compared to what I expected going in. One thing it has got worse at: Conqueror's Haki. It used to be drawn hard, like lightning cracking off the character. Lately it is soft and washed out. It reads as less of a threat than it used to.