Driven by winds near 45 miles an hour early Monday morning, a fire that started north of Calistoga raced over the hill into the Fountaingrove business district, obliterating some structures while miraculously sparing others nearby. The fire’s intense heat turned cars and buildings into melted piles of rubble and ash.

Keysight Technologies, one of the largest employers in the Fountaingrove area with about 1,100 employees on its campus, had three structures burned near Building 1, including Vista East, Vista West and a school, but most of the campus appeared intact. All four of Keysight's main buildings survived the flames. An emergency response team from Keysight was already on the site Tuesday morning.

The fire jumped over Mendocino Avenue and wiped out the Kmart store and the Journey's End mobile home park. But businesses in the same business park nearby were untouched by flames.

These are photographs taken in the Fountaingrove district as well as across Mendocino Ave. on Tuesday, the day after the fire's destruction.