It connects the cities of Tateyama and Kisarazu, spanning the Bōsō Peninsula in a south–north routing.

It travels south from there towards the southern tip of the Bōsō Peninsula, Cape Nojima.

Upon reaching the cape, the highway begins curving to the north heading through Minamibōsō and the former town of Chikura.

[5] Construction began on the Kururi–Makuta Bypass of the narrow sections of the highway including the Yomachisaku Daiichi Tunnel in 1989.

[2] On 23 December 2015, a 20-meter-long (66 ft) section of the Yomachisaku Daiichi Tunnel's shotcrete lining collapsed following a re-application of the supportive lining a month prior to the collapse.