I revisited the park in November 2022, exclusively exploring the "Painted Desert" North Entrance area of the park (after allocating more time via the South Entrance in 2010). Hiking the easy, yet rewarding Painted Desert Rim Trail (1.2 miles) from Tawa Point to the Painted Desert Inn/Kachina Point is an essential experience during the magical hour before sunset. The Painted Desert Inn (built 1937-1940) just off the original alignment of Route 66 is a historic gem of Pueblo Revival Architecture, which includes designs from Mary Jane Colter (also known for her 'Parkitecture' properties at the Grand Canyon). The Painted Desert Inn is a National Historic Landmark. 

The Petrified Forest National Park has doubled in size since the early 2000's. Much of the expansion land was already being authorized even as the 2008 nomination was officially added to the US Tentative List (from 93,533 acres to 221,390 acres). The values of the park are perhaps more diverse than the originally proposed criteria (vii, viii). I would much prefer the nomination (when and if it comes to fruition) to seek inscription based on cultural and natural criteria. Here is the US ICOMOS World Heritage Celebration Video highlighting the OUV of Petrified Forest National Park. 

For travellers wishing to explore the parks wilderness areas, such as Devil's Playground (three permits are available each week on a first-come-first-serve basis at the Painted Desert Visitor Center only). Additionally, there are also plenty of longer hikes that offer rewarding experiences, such as the Onyx Bridge Hike (4.6 miles). I know for my next revist, I will be looking at one of these opportunities with excitement.