Visit the biggest of all Humboldt dunes, a sprawling, 1 million-cubic-yard sand mountain barely  contained by the Ma-le’l Dunes Cooperative Management Area. Jointly supervised by the Bureau of  Land Management and the Humboldt Bay Wildlife Refuge, this federal preserve features rare coastal 

plants and animals, a spooky skeleton forest and, once one trudges to the top of said dune, panoramic  views of ocean, bay and inland mountains. Look for beach strawberries, sea rocket plants and rare  Humboldt Bay wallflowers, or crisscrossing tracks left at night by foxes, skunks and raccoons. The  southern unit, which permits horses and dogs, is open daily. The northern unit, which offers more direct  access to the monster dune, is open weekends.