The San Diego Humane Society says the kittens somehow wound up inside a 60-foot steel column that was trucked from Hayward in the San Francisco Bay Area to San Diego.
On April 24, construction workers building new Kaiser Permanente medical offices heard meows coming from the column.
They tilted the column and the week-old kittens slid out. It's unclear whether the stowaways came aboard in Hayward of somewhere along the route.
The kittens are now in foster care and will be ready for adoption in another couple of months.
And they've been given appropriate construction names: Crowbar, Rebar, Chisel, Jackhammer and Piper.
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