Tickets for Deck the Alley can be found here: https://elfrethsalley.ticketleap.com/deck-the-alley-2019/
Look up Fete day. As an addendum: "Dating back to the 1930s, this traditional celebration is the only opportunity of the season for visitors to actually step into the private homes of Elfreth’s Alley and discover how generation after generation have continued to preserve, alter and add to these historic structures." Usually in June.
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