In New York, "Summer Streets" is set to debut this August. In Portland, they just held "Sunday Parkways" for the first time. Streetfilms’ Clarence Eckerson, in town for the Carfree Cities conference, captured the action and picked up a few pointers for other cities planning to launch car-free events:

It was like a giant community block party with walkers, bikers, joggers, bladers, families, and pets filling the 6 mile course.

There were plenty of fun activities in four northeast parks that
were linked by the circuit, which was opened to bikes and pedestrian
traffic only from 8 AM to 2 PM. For cities planning their own
Ciclovias, here are some things I liked about Portland’s event:
knowledgeable volunteers, lots of fun chalk messages on the ground,
easy to follow directions, lots of music & entertainment, and a
huge number of bike stations for bike repair.