On a freezing desert morning three years ago I finally learned what Nancy Holt's earth sculpture Sun Tunnels is about.

A motley mob of about 30 shivering people, many wrapped in blankets, were waiting for the summer Solstice sunrise. Let’s face it, four sections of concrete culvert lying in a cross configuration in the desert near the ghost town Lucin is not all that impressive—let alone artistic, when a freezing wind is whipping across the desert. Small wonder that even few Utahns have experienced it.

The group included a family who had changed their surname to Gaia and a old "desert rat" from Nevada. We watched in suspense the daylight climb a ridge behind us while the sun itself remained hidden behind a mountain range to the east. Then suddenly the sun popped out and crawled atop a nipple-shaped peak. Its warming light streamed perfectly through the center of Holt's tunnels. Just as it does, without fail, twice every year.

The bloody sky and solar disc were staggeringly beautiful, but that was the least of it. Revealed to the crowd was the clockwork intricacy of the cosmos. That the whirling stars, moon and sun foretell the seasons is something our ancestors understood intimately, but it’s something we've mostly forgotten because we've been separated from it by technology, artificial light and vinyl siding.

I had seen Sun Tunnels a few times before, but not on a solstice dawn. Timing makes all the difference to lonely, manure-dotted land art.

Nancy Holt died last week, she was 75. It's unfortunate that Holt is best known as the wife of Robert Smithson who created the Spiral Jetty in the Great Salt Lake 40 miles south of her Sun Tunnels. (Smithson was killed in a plane crash in 1973.) Holt's land art is equal her husband's—and both are found in northern Utah. Sun Tunnels and Spiral Jetty require a serious journey to experience and both bring humans back, again and again, (it's that spiral thing) into alignment with with nature and the awe-inspiring land around us.

Here's what the Sun Tunnels look like to Google Map's eye in the sky.

Prepare for your trip to the Sun Tunnels by spending an afternoon at the Utah Museum of Fine Arts' new exhibit that creatively explores  the land that surrounds us. It includes Great Salt Lake Landscan by the Center for Land Use Interpretation and a new take on Smithson's creativity by British artist Tacita Dean. The shows end May 4.