Unbeknownst to us - every Tuesday at noon, 65 air raid-style sirens around San Francisco sound off for 15 seconds, as a test for an emergency warning system. This began in 2005 after a refurb of their WWII system, following the 2004 Tsunami.
I was happily enjoying an idyllic picnic with the girls atop of Corona Heights and assumed the worst - we decamped at speed down rocks and screed, noting a dog walker exodus below. We were heading for the wooden steps, pondering how to position ourselves if this was an earthquake warning, when thankfully a local man halted and calmed us down. Midday must be shift-change in the pooch park too.
Down below in the Randall Museum were lego sets on shaker pads, so you could test your structures strength in the face of these routine tremors.
