Summer Solstice Marker

The Ancestral Puebloan people who lived along the Puerco tracked the sun with stone. Near this spot a spiral petroglyph was carved so that for about two weeks around the June solstice, a shaft of light slides down a cleft between boulders at sunrise and touches the spiral's center within minutes of nine o'clock. It is a calendar built into the desert, precise enough to mark the year's turning for a farming people whose planting depended on reading the seasons. Archaeoastronomers call such alignments sun daggers; the makers simply called it knowing when to plant.

What the plaque says

A solstice is an astronomical event that happens twice annually as the Sun reaches its highest or lowest point in the sky. Here in the Northern Hemisphere, June 20th is usually the longest day of the year and is referred to as the summer solstice., These photographs illustrate how sunlight from the rising summer solstice Sun flows down the cleft in the boulder in front of you. The play of light and shadow on the spiral petroglyph changes as the Sun rises and moves across the sky. From between June 14th to the 28th a shaft of light forms, moving down the side of the adjacent boulder, until it touches the center of the spiral within a few minutes of 9:00 am.

Where it stands

Worth the stop nearby

• Petrified Forest National Park — 4.8 mi
  Two hundred million years turned to stone — and a Route 66 ghost
• Holbrook — 21 mi
  A Santa Fe railroad town once too tough for women and churches, now the seat of Navajo County, gateway to the Petrified Forest, and home to the concrete teepees of the Wigwam Motel.

More markers nearby

• Newspaper Rock Petroglyphs — 0.9 mi
• Pioneers of Paleontology — 2.3 mi
• Agate Bridge — 5.7 mi
• The Painted Desert — 6.1 mi