Drive along First Avenue North, just on the other side of the railroad tracks from Regions Field downtown, and you might notice Innovation Depot. This is a business incubator that’s done a lot in recent years to spur entrepreneurship in Birmingham. But it’s actually part of a larger innovation district. Most people haven’t heard of Birmingham’s innovation district, but some city boosters say it is finally ready to take off. We talk about that in this week’s Magic City Marketplace.