Heavy industry in cars.
Boom in the 1950s to a population of roughly 2,000,000. Deindustrialisation meant there are now under 800,000 people. This was as things were being produced more cheaply elsewhere.
Some companies were bailed out by the government, some were not.
People cannot afford housing, so Detroit is now a ghost town. People cannot live in well established neighbourhood.
In 1958 the Packer Plant was abandoned. Michigan central station was abandoned in 1988.