Alias /gallery3 /usr/share/gallery3

<Directory /usr/share/gallery3>
  Options FollowSymLinks
  AllowOverride Limit Options FileInfo
</Directory>

# some people prefer a simple URL like http://gallery3.example.com
#<VirtualHost 1.2.3.4>
#  DocumentRoot /usr/share/gallery3
#  ServerName gallery3.example.com
#</VirtualHost>