The sun-scorched confluence of the Snake and Columbia Rivers marks the end of a straight-shot journey along Highway 14 and the Columbia Gorge. Here you’ll find an industrious trio of cities—Kennewick, Pasco, and Richland—at the rivers’ junction. The Tri-Cities are book-ended by the Yakima and Walla Walla Valleys, surrounded by bountiful fields of potatoes, grains, fruits, and veggies, much of which is exported to Pacific Rim countries.

So how does a collection of agricultural towns grow into a metropolitan area with more than 120,000 people? The answer lies north of Richland at Hanford Site, birthplace of the Manhattan Project and home to the decommissioned nuclear munitions plant whose cleanup has funneled more than $12 billion into the local economy.

Lucky visitors can get an up-close look at selected portions of Hanford site during limited tours offered by the Department of Energy.

Getting to Tri-Cities

Public transportation comes together at the Transportation Depot (535 N. 1st Ave.) in Pasco. Here you can catch a local bus from Ben Franklin Transit (509/735-5100, www.bft.org, $1, $2.75 all day pass) for service to the three cities and the airport Monday–Saturday.

Greyhound (509/547-3151 or 800/231-2222, www.greyhound.com) also stops here, as does Amtrak (509/545-1554, 800/872-7245, www.amtrak.com), whose Empire Builder train provides daily service east to Spokane, Minneapolis, and Chicago, and west to Portland.

Departing from the Tri-Cities Airport in Pasco—the oldest airport west of the Mississippi—are Horizon Air (509/547-6352 or 800/547-9808), Delta Air Lines (800/221-1212, www.delta.com), and United Express (800/241-6522, www.ual.com).

Bergstrom Aircraft (509/547-6271) offers flightseeing trips out of the Richland airport over the Tri-Cities area for $99 for up to three people on a Cesna 172.

Columbia River Journeys (509/734-9941 or 888/486-9119, www.columbiariverjourneys.com) runs jetboat trips to Hanford Reach. As you cruise up the river, you’ll see heron rookeries, curious coyotes, huge salmon beds, and the surreal Hanford reactors along the horizon.