During the California heat wave of 1906, Baldassare Forestiere , A Sicilian immigrant born in 1990 had 80 acres in Frseno, where he dug a home underground with just a pickax and shovel. He spent 40 years excavating 10 acres of rooms, tunnels, a chapel, an underground aquarium, and courtyards to experiment with underground farming.

The hardpan, a cemented layer in the soil, 2 feet under the surface, made it impossible to farm. With no budget, he mixed mortar from the dirt he dug out, creating his own concrete and bricks. Despite continuing to work as a day laborer during the day (mostly digging irrigation ditches), by the 1920s, he had completed about 50 subterranean rooms.

Despite having just a fourth-grade education and no architectural training, Forestiere – inspired by the catacombs of Rome – built arches for support, and to this day, none of his underground construction has collapsed. In areas where he wanted more natural cooling (like near stoves), he created cone-shaped openings to encourage the venturi effect, pushing the hot air out and sucking the cooler air down.

He also experimented with underground farming, and was able to grow a variety of fruits and vegetables. He grafted up to 6 varieties of fruit on one orange tree rootstock.

It is now The Forestiere Underground Gardens | Historic Site in Fresno

Land was barren. He dug 10-acre underground village & orchard - Includes a description and link to 45 min video | FairCompanies
Forestiere Underground Gardens | Wikipedia