Violence killed the historic gay Halloween party in SF’s Castro.

An estimated 500,000 people packed the Castro on Oct. 31, 2006. It would be the last mass Halloween gathering in the neighborhood. (Photo: Carlos Avila Gonzalez)

“When you have a historic event, you can’t just stop them, because people will still show up,” then-San Francisco Mayor Gavin Newsom said on Nov. 1, 2006, the day after 9 people were shot amid a chaotic throng of half a million partygoers…