A group of about 40 American Indians and allies carried banners and flags as they made their way north through Sonoma County on Day Four of a 4,000-mile journey to Washington, D.C.

Staying when possible on the trip at reservations, and making stops at the Standing Rock encampment in North Dakota and Wounded Knee, South Dakota, the group plans to arrive in Washington on July 15. Officially called “The Longest Walk 5,” the group left San Francisco’s Crissy Field on Sunday on the first stretch of the walk across the country. The first Longest Walk was in 1978. This year’s walk is meant to raise awareness about domestic violence and substance abuse.

Bobby Wallace, the Longest Walk’s national chief, said the group’s size will wax and wane as it makes its way across the country, but the idea is to piggyback on the unity felt at Standing Rock, site of the Dakota Access Pipeline where months of protests have occurred.

You can reach Staff Writer Christi Warren at 707-521-5205 or christi.warren@pressdemocrat.com. On Twitter @SeaWarren.