Can I substitute another attraction for the Skywalk Observatory ticket included in my Boston CityPASS? August 10, 2020 21:36 Updated Yes, since Skywalk is permanently closed, the Franklin Park Zoo will accept your Skywalk Observatory ticket. Related articles Boston CityPASS Attraction Schedule Updates Atlanta CityPASS Attraction Schedule Updates How do I upgrade my Empire State Building ticket with New York CityPASS tickets or C3 tickets? New York CityPASS Attraction Schedule Updates How long does it take to receive a CityPASS booklet?