One of the best rides I've found so far, is in the Texas Hill Country, northwest of San Antonio. Ride out through several little towns like Bandera and westward to Leakey. There are three Texas Farm to Market roads, numbered 335, 336 & 337. These are known as "The Three Twisted Sisters".
It just don't get no better than that. I'll bet that Wiredgeorge will confirm this. He lives between Bandera and San antonio.