In NYC one of the newest and most popular parks is called "The Highline". A stretch of unused elevated rail line converted into a long narrow winding park. http://www.nytimes.com/2016/09/12/us/atlanta-beltline.html
The NY Times article says it best:
"The High Line in New York, which turned an elevated stretch of Manhattan rail line into a linear park, is perhaps the best known of the nation’s urban infrastructure makeovers. Chicago’s has also converted an old elevated track into a greenway, christening it the 606. Miami’s Underline is reimagining 10 miles of underused land under its elevated Metrorail system as an art-lined “urban trail.”
|NYC's "High Line" Park|
|Another view of NYC's "High Line" Park|
"Private investment along the entire proposed route [of Atlanta's Beltline] has surged to $3 billion. Foundations and private donors have given more than $54 million for paths, parks and other amenities. Home prices have risen in formerly overlooked working-class neighborhoods where the BeltLine is set to expand."
People don't just like parks - they love parks. And it raises property values and makes people want to move back into cities.