While decidedly not as grandiose and exotic as some other Kasbahs in the region, the Taourirt Kasbah has it's own merit and is definitely worth a visit if you're in Ouarzazate. It's be completely restored and is in (what I can imagine) similar shape as it was in its heyday hundreds of years ago.
It's right at the edge of town and easily reached in a "petiti taxi"...the entrance costs 10 Dirham (around one dollar) and you'll of course be offered plenty of "guided tours," which I'd suggest turning down with a smile and a polite "la shokran" ("no thanks" in Moroccan Arabic). The building itself is like a maze. Each floor is filled with tiny corridors and passageways and multiple staircases, and the fact that many of the rooms are empty or unadorned might lead you to breeze on through. Big mistake. Right when you think there's nothing special, just more empty rooms, you stumble on an amazing chamber with Arabic engravings, gorgeous original tilework, and impressive views of the surrounding Kasbah.