National Park Service Centennial covers

There are sixteen separate designs from @McGeekiest Cachets for the National Park Service Centennial issue. Each cachet features a different public-domain photograph taken in the park featured on the accompanying stamp, digitally warped into a sphere. A green arrow trace makes a right-angle turn in the lower-left corner, tipped with a stone arrowhead. The name of the park is printed above the line in a chiseled-stone font. Each cover is canceled with the black-and-white first day of issue pictorial postmark dated June 2, 2016 in New York City. Only five sets were produced.