I'm a big fan of cities. I even went to graduate school for city planning. But I'm well aware that cities can be hard on people mentally. One of the most critical pieces of a healthy city, in my opinion, is a good number of parks. These are not just useful for superficial recreation and a premium view. These help residents psychologically and are worth a great deal.
In fact, a study from the University of Wisconsin has found that green space is more important than money. A poor person living near greenery was even more likely to have a self-reported higher level of peace and happiness than a wealthier person living in an area with less greenery.
To be specific, if someone lived in a neighborhood with 10% less tree cover, they were more likely to report signs of depression, anxiety, and stress.