Authorities told WSB-TV that they were contacted by the Elizabethtown Police Department in Kentucky about the arrest of Joseph Bryan Capstraw, 20, who said he met the woman at the gathering in Lumpkin County.
The Rainbow Family is a name for a very loose collection of self-described misfits, nature-lovers and artists who gather once a year in a national forest. This was their 47th gathering, but the first in Georgia.
According to authorities, the woman accompanied Capstraw as they left, hitchhiking from the event.
The Sheriff's Office says they need to identify the woman so she can be returned to her loved ones.
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WSB-TV's Michael Seiden covered the gathering near Dahlonega. Many of the people he met on assignment told him they do not go by their legal names during the event. That could prove to be a challenge for investigators.