NEW YORK (CBSNewYork) -- The World Trade Center is in the midst of a transformation since the 9/11 terrorist attacks.
The new exterior is just the beginning. Inside the shiny new buildings, a radically different culture has taken over.
High above Lower Manhattan, with skyline views once reserved for bankers and lawyers, graffiti artist Michael Grimace lets loose with a can of spray paint inside 4 World Trade Center.
"I have painted in a lot of unique places in New York and around the world and this has to be literally at the top of uniqueness," he said.
The tower is one of the newly finished buildings that rose from the ashes of 9/11. Today, the 69th floor is a colorful collaboration of street artists, now working here for free.
One of their biggest fans visits in a pinstripe suit and pocket square. Billionaire developer Larry Silverstein took the lease at the building just two months before the 9/11 attacks and has overseen the rebuilding of Lower Manhattan.
The newest residents are the modern titans -- high-tech giants like Spotify which leases 14 floors at the building.
Dr. Kenneth Ouriel's high-tech healthcare research company Syntactx recently moved in.
"When you get a company like Spotify and you get young people, I think it makes it easier for us to recruit young, intelligent people that are at the start of their career," Ouriel said.
Silverstein not only accepts this new vibe, he embraces it.
"So are the days of the World Trade Center being a buttoned up financial hub over?" CBS2's Kenneth Craig asked.
"Totally changed," Silverstein said.
Now 86, Silverstein watched the original Twin Towers go up and then come down. Sixteen years later, he sees a transformation from darkness to light and color.
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