The 6 train stops at 28th Street on Park Ave So and 33rd Street on Park Ave, each about two blocks away. From 33rd Street, Grand Central is one stop north. Going south, the 6 reaches Union Square in two stops and SoHo not long after.
A few minutes west, the N, R and W run along Broadway at 28th St. Herald Square, at 34th St., connects to most of the rest of the system, including the B, D, F, M and Q.