When games we're just plain fun. Ah, memories...
The gameplay was simply stuning, there was enough weapon variety and replay value to play the game over and over again. The maps and visuals were pretty repetitive, but that was what actually made it interesting. We thought we memorized each corner, each secret passage way(and the game had a lot of them), and yet some classmate finds another secret, it was never ending fun.
If I remember correctly, it had quite a few bosses, and there we're all unique in their own way, and most games nowadays lack exactly that(yeah, I'm looking at you Batman: Arkham Asylum). There were half robot hybrids with machine guns instead of arms, and there was even Hitler himself.
The sounds and story-line didn't matter, it was the actual g-a-m-eplay that mattered. And that, ladies and gentelmen, what makes a game.
Wolfenstein 3D is just nostalgia for some now, but for others, it's still a pretty damn good game.