Phoenix ranks just behind Dallas and Fort Worth for the amount of undeveloped land, and much of it is government-owned. According to a CommercialCafe report, Phoenix has more than 53,000 acres of vacant land and nearly 16,000 parcels. Some land is owned by the city, but much of it is state-owned, which requires would-be buyers to request an auction. But the city is seeking proposals for affordable housing on some of its parcels.
Source: https://www.bizjournals.com/phoenix/news/2023/04/06/phoenix-among-us-cities-with-the-most-vacant-land.html
