I know some people who play and read these types of game today aren't a fan of this type of game. But really, this one did start it all. I played, learned, and liked the original two-word parser.
Really, even if you've read and played a lot of other types of IF, you really should find a way to play this one. Sure, it's a simple parser, but the adventure is fantastic. No, there's no huge storyline. But finding your way around and learning your way through this massive cave just can't be beat. Try it. Really.