These are the dates for 2019.
March 31st, April 21st, May 19th, June 9th & 23rd, July 14th & 28th, August 11th & 25th, September 15th & 29th and October 20th. All these dates are on a Sunday.
May 4th (2 seats left), July 6th (sold out), September 7th (very limited) and October 5th.
Tickets go on sale December 1st, walking tour vouchers available now and will be valid for next season.