Riesling wines rank among the top three white wines along with Chardonnay and Sauvignon Blanc.  Riesling wines can range from crisp, fruity, with low alcohol to rich sweet wines with high alcohol levels.  They are rarely oak aged.  Riesling wines are extremely expressive of its terroir, which means there is wide variation in flavor and intensity from one Riesling region to another.   They are grown in Germany, Alsace, Austria, Australia, and California.   Riesling wines tend to have flavors and aromas of green apples, lemon, peach, passion fruit, lime, lychee, guava etc.