OAKLAND, Calif. — One wonders if Gertrude Stein would write “there is no there there” about Oakland if she could see the thousands of people who convene every month for this city’s rambunctious art crawl and street bacchanal.

Actually, there is an abundance of there here: what started six years ago as a small, once-a-month gallery walk has mushroomed into an event that city officials now say attracts as many as 20,000 people downtown for an evening known as Oakland Art Murmur.

“This is definitely more like a shout,” John Herbstritt, 26, a wine buyer who recently moved to Oakland, said as he looked at block after city block of overflowing galleries, street musicians, food trucks and curated art exhibits last Friday.

Visual enticements were everywhere, like shiny lowrider cars and a scantily clad pole dancer atop a jalopy with a black metal unicorn head.