Family lore has it that Dwight D. Eisenhower decided to create the nation’s interstate highways after spending 62 long days traversing the country in an Army convoy in the 1910s.

Ike’s great-grandson Merrill Eisenhower Atwater will duplicate that road trip this month, but he’ll be blogging about his travels from an air-conditioned coach, in commemoration of the 50th anniversary of the American highway system.

“As I got older, I started to realize the significance of Dwight David Eisenhower and what he did for the country,” said Atwater, a 25-year-old communications and history major at Missouri Western State University in St. Joseph, Mo.

On Friday, Atwater, along with “The Bachelor” star and Firestone tire company heir Andrew Firestone and highway chronicler Dan McNichol, left San Francisco on a convoy crisscrossing the 46,508-mile interstate highway system. They’ll finish June 29 in Washington, D.C.

Atwater will post his opinions daily at www.interstate50th.org.

The route follows in reverse the 3,000-mile journey President Eisenhower took in 1919, which in his autobiography he called “Through Darkest America with Truck and Tank.”