NARRATOR
You're standing in Levi's Plaza, its fountain cascading over granite blocks facing Telegraph Hill. Just about everything you see apart from the hill itself arrived quite recently. The fountain and Plaza were built in 1980. If you could peel back the layers of concrete below, you'd find remnants from earlier times, warehouses, a Gold Rush era wharf, and under that, layers of mud and sediment deposited over thousands of years. But much older by far is the sandstone of Telegraph Hill. This rock, known as greywacke sandstone, was born about 130 to 135 million years ago, during the Cretaceous, dinosaur times. Deep beneath the ocean, two tectonic plates were colliding. The Farralon plate was forcing itself underneath the North American plate, creating an underwater trench along the junction.
From time to time, sandy sediments would come tumbling down into the trench in massive underwater landslides. This created a layer of sandy soil that hardened over millions of years into greywacke sandstone. Millions more years later, it was pushed upward to become part of Telegraph Hill, as well as Rincon Hill, Nob Hill, Russian Hill, and Alcatraz Island. Once the hill formed, it stood quite peacefully for thousands of years, touched only by the weather, plants, animals, and Indigenous peoples, its shape largely unchanged. Then in the late 1840s, when arriving cargo ships wanted a place to offload their cargo, European immigrants began digging away and later blasting away at the sandstone hillside.
JAMES DELGADO
Telegraph Hill, with its massive stone, was early whittled away to make a more firm platform and flatter ground for the warehouses that were constructed at its base.
NARRATOR
Archaeologist James Delgado.
JAMES DELGADO
As more flatland was needed, Telegraph Hill was quarried away. That stone was not only dumped into the Bay, but it was also placed inside ships as ballast that helped stabilize them. And so it was that Telegraph Hill became one of the best traveled pieces of San Francisco.
NARRATOR
To this day, remnants of Telegraph Hill can be found in Valparaiso, Chile. The sandstone was relatively easy to quarry, and so was used to construct streets, buildings, and San Francisco's first seawall in 1867. Among the excavators of Telegraph Hill were the notorious Gray brothers, George and Henry Gray. In 1887, they set up a quarry at Green and Sansome streets, breaking up the sandstone to make cement. They quarried so relentlessly that the hill turned into a precipitous cliff. Homes along the summit would shake with every dynamite blast. In 1895, after a house slipped off its foundation, a judge ruled that the Gray brothers had to stop. But using money and political connections, they found ways to continue carving away at the hillside. Their digging finally ended in 1914, when a disgruntled worker unable to collect his back wages shot and killed George Gray. Their legacy can be seen in Telegraph Hill's extremely steep cliffs, where boulders still come tumbling down from time to time. This site boasts more than just a view of Telegraph Hill. Continue on to hear about what the archaeologists discovered in this very Plaza.