Petrified Forest National Park

Petrified Forest is a park of deep time and hard evidence. Two hundred and twenty-five million years ago, in the late Triassic, this was a tropical floodplain near the equator on the supercontinent Pangaea, forested with conifers up to two hundred feet tall. When the trees fell, floods buried them under silt and volcanic ash before they could rot; silica from the ash seeped through the wood cell by cell and crystallized into quartz, stained with iron and manganese. What is left are whole logs turned to stone — jasper, agate, amethyst — scattered across the badlands, ringing like rock when you tap them, some lying where they fell before the dinosaurs.

The badlands themselves are the Painted Desert: banded hills of the Chinle Formation running red, orange, and violet, the same soft clay the fossil logs weather out of. It was never only geology. Ancestral Puebloans farmed and built here too — the hundred-room Puerco Pueblo, and Newspaper Rock, a boulder crowded with six centuries of petroglyphs — people ancestral to today's Hopi and Zuni. It became a national monument in 1906, when rail travelers were hauling the fossil wood away by the ton, and a national park in 1962.

There is one more layer, thinner and stranger. Petrified Forest is the only national park that a stretch of Route 66 ever crossed, and the old road is gone — no pavement now, just a line of leaning telephone poles and a rusted 1932 Studebaker set out to mark where the Mother Road ran. The park still closes its gates at night, partly to keep people from pocketing the wood; the rangers keep a file of "conscience letters" from visitors who took a piece, had nothing but bad luck, and mailed it back with an apology. It sits just east of Holbrook, and the pueblos here point north toward the Hopi mesas.