Millions have been spent over several decades to stabilize its steep slopes, including a $1.9 million project that was celebrated in 2000. Cases of landslides go back to at least 1846 and 1859, when The Sun reported one that piled earth 6 or 8 feet deep at the bottom of the hill’s north side. In 1916, The Sun reported heavy rain caused an “avalanche” of earth to spill onto the street in the same area as Thursday’s landslide.