Tag der Stadttore will be held on August 22nd from 10:00 to 16:00.  There are free guided tours at 10:30, 12:00, 14:00 and 15:30 at the Spalentor, St Johanns-Tor, St Alban-Tor and two military sites on the old preserved city wall.

For full details please visit the website http://www.stadttorebasel.ch/