Walla Walla County [Washington] is better known for wheat fields than Wi-Fi. But a small community-owned utility in this agriculture-dependent region has constructed one of the largest wireless Internet networks in rural America, rolling out high-speed connections across about 1,500 square miles.

Dayton-based Columbia Energy, a subsidiary of the Columbia Rural Electric Association, built the network for farmers who monitor irrigation equipment in the field and for residential and business customers who have limited access to cable or digital subscriber line service.

“You have some hot spots at Starbucks,” Columbia Energy CEO Tom Husted said. “This is one huge hot spot.”

Huge it is. The network is 10 times larger than a proposed citywide Wi-Fi (wireless fidelity) network in Philadelphia — one that media reports last week inaccurately said would be the largest in the world. Covering parts of Walla Walla, Columbia, Franklin, Benton and Umatilla counties, Columbia Energy’s 1,500-square-mile Wi-Fi hot spot is bigger than the state of Rhode Island.