Arizona's Petrified Forest is a graveyard of ancient tropical groves and human history

Countries & Cities · Published 30 September 2026 Swipe more like this →

In short: Spanning 346 square miles in eastern Arizona, this national park preserves more than just fossilized wood. It is a high-desert landscape where the remnants of Triassic-era forests meet the ruins of Ancestral Puebloan civilizations, offering a rare window into deep geological time and the resilience of early human inhabitants.

Established as a national monument in 1906 and upgraded to a national park in 1962, the Petrified Forest is defined by its dramatic, wind-eroded badlands. The northern section extends into the Painted Desert, a region of vibrant, colorful hills. The park's geological story is rooted in the Triassic Period, roughly 201 to 252 million years ago, when the area was home to lush tropical groves. Today, these ancient trees are preserved as stone, alongside fossils of phytosaurs and early dinosaurs.

The park's human history is equally profound. Archaeological evidence shows that the earliest inhabitants arrived 13,000 years ago. By 2,500 years ago, Ancestral Pueblo farmers were cultivating corn in subterranean pit houses. Over time, these communities transitioned to masonry dwellings, such as the Puerco Indian Ruin. By 1450 CE, these populations migrated toward the Hopi Mesas and the Pueblo of Zuni, where their descendants continue to reside. Today, more than 1,000 archaeological sites, including intricate petroglyphs like Newspaper Rock, remain protected within the park boundaries.

Managing this vast area presents unique challenges. While the park proper covers 146 square miles, administrative acquisitions since 2005 have expanded the total protected area to 346 square miles. This includes a mix of federal, state, and private lands. The environment is harsh, with elevations averaging around 5,800 feet and annual precipitation typically falling below 10 inches. Despite the lack of overnight lodging, the park remains a vital site for paleontological research and a testament to the enduring connection between the land and its ancestral stewards.

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