North Cascades Loop - The Most Scenic Drives in America: 120 Spectacular Road Trips - page 72

Continuing on S.R. 20 to the mainland, the Cascade loop ends where it began—in
the fertile Skagit Valley. Here the moist lowlands abound with truck and dairy farms and
are abloom each spring with whole fields of daffodils, irises, and—most famously—the
world's largest crop of tulips.