By Heather Lee

We’re a nation of java junkies—nearly eight out of 10 Americans drink coffee. Want to know what’s behind your cuppa joe? Take a tour from one of the coffee purveyors listed below.

CARAVAN COFFEE Newberg, Ore. Starting at the blending station, examine 30 varieties of raw beans. Check out the packaging station and stop at the espresso training facility, where you’ll be treated to a brewed beverage of your choice. No charge for the tour; free cupping seminars also available. (800) 875-5282,www.caravancoffee.com.

COFFEE ROASTERS OF LAS VEGAS Las Vegas. Take the "10-cent tour"—it’s actually free—and learn everything about the roasting process, including how beans are decaffeinated. Samples of coffee (and tea, too) await at the conclusion. (702) 435-9338,www.coffeeroastersoflasvegas.com.

HOLUALOA KONA COFFEE COMPANY Holualoa, Hawaii. Get an up-close look at a working coffee plantation in the Aloha State’s famed Kona coffee region. You’ll get the scoop on different grades of beans from the prized peaberry to the less-than-stellar Triple X. (808) 322-9937, (800) 334-0348, www.konalea.com.

LONGBOTTOM COFFEE & TEA Hillsboro, Ore. Learn how the company’s hot-air roasting method produces bitterness-free beans. Be sure to grab a goody bag stuffed with samples at the end of the tour. (800) 288-1271, www.longbottomcoffee.com.

PEABERRY'S COFFEE & TEA Emeryville, Calif. Watch a 45-pound batch of green (raw) beans develop their dark color—it usually takes about 20 minutes. Free tours are given on roasting days so visitors can see the machines in action. A coffee-tasting seminar in the cupping room tops off the tour. (510) 420-0473.

PLANTATION COFFEE ROASTERS Elk Grove, Calif. Learn the skill of slurping, spitting, and tasting coffee like a pro under the tutelage of owner Dan Davis. His cupping class also includes roasting demonstrations, a coffee-education PowerPoint lecture, and cheesecake from the on-site bakery. Class $24. (916) 714-2633, www.plantationcoffee.com.

SACRED GROUNDS Arcata, Calif.After a free tour of the roasting area, stay for a coffee-cupping session, during which hot water is poured over coarse grounds in a whiskey tumbler. You’ll learn to evaluate aroma, acidity, body, flavor, and aftertaste. (800) 425-2532, www.sacredgroundscoffee.com.

WHITE CLOUD COFFEE Boise. Listen while a 150-pound batch of fresh beans shuffles through the roaster during the complimentary tour. Guides will also clue you in on how coffee gets its hazelnut, huckleberry, and chocolate raspberry flavors. (208) 322-1166, (800) 627-0309, www.whitecloudcoffee.com.