It is an account of MacNiven's journey walking and backpacking the entire length of Japan from Kyūshū to Hokkaidō, more than 2000 miles in 145 days.
Inspired by their story, MacNiven conceived of the task after learning that his father, whose parents were foreign missionaries, was born in an unknown location in Hokkaidō.
Armed with a desire to impress Ayumi and find his father's birthplace, as well as an interest in Japanese culture, MacNiven set sail to Japan.
Although he completed his task in July 2004, it was not until the subsequent year that Kintaro Walks Japan was disseminated on the internet and gained popularity.
Unable to find a distributor for the documentary of the trek, MacNiven burned 1,000 DVDs and began hawking copies of the film on the streets of San Francisco and at a restaurant his father owns.