Larry Silverstein knows where the young people hang out. According to the 85-year-old, the place to be is Lower Manhattan — where Silverstein Properties just developed 30 Park Place, a Robert AM Stern-designed condominium. For that reason, Silverstein and his wife Klara, are moving from their Park Avenue digs to the building’s 80th floor, the Wall Street Journal reported. The move will shorten his commute to 7 World Trade Center to under four minutes.