'Subway Therapy' invites commuters to scribble their thoughts on colorful sticky notes and then share by pasting them onto subway passages. In time, the walls become canvases blooming with color.

However, graffiti has existed even longer, dating back to ancient Egypt, Greece, and the Roman Empire, where inscriptions and carvings were etched into walls ... it was New York’s subway ...

In downtown New ... walls. Periodically, the crew would force a metal rod up through the soil to the road above to check that they were on course. It is hard to keep a secret in New York City ...

Over the past few weeks, renowned British street artist Banksy has taken New York City by storm, leaving a trail of spray paint in his wake. But graffiti is nothing new here: The city has long ...