FREMONT (CBS SF) – The homeless crisis in the Bay Area has reached new heights, literally, as transients live in tree houses in Alameda County.

Neighbors in Fremont say it began with one, but as word got out there are now at least five or six of the structures nestled high in the branches of a row of eucalyptus trees in an industrial park in Fremont.

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Getting up to the structures is no simple task. Some are three stories up.

Climbing up is a lot like solving a puzzle. Once inside, you can get a better look at the craftsmanship. Whoever did it likely has some experience at construction and access to power drills. They have cross beams, support beams underneath, and support straps above.

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Trash? There’s a spot for that.

Neighbors tell us they use scrap wood from nearby discarded pallets.

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