Woodruff.
If anyone is going "to" Woodruff, they're going to the small town in Spartanburg County -- possibly to Claudio's Bistro right there on Main Street, which serves a mean ahi tuna.
If anyone is "on" Woodruff, or talking about the "Woodruff shitshow," or advising others to "stay the fuck off Woodruff," they're talking about the major road that runs east and southeast from its terminus at Laurens Road through the most suburban parts of Greenville. Woodruff Road is a horror where nearly every major commercial enterprise in Greenville is either located on Woodruff or has a branch there. Traffic clots solid starting at rush hour in the morning and doesn't let up until rush hour in the evening is over. People will plan their entire days, errands, and shopping around avoiding Woodruff Road or at least figuring out an alternate route home from Woodruff that spends as little time on Woodruff itself as humanly possible. It's so bad that the city, county, and state are collaborating on building a parallel parkway, cunningly named
Parallel Parkway, that will run alongside Woodruff and take some of the through traffic off of it.
Laurens Road is another road in the same vein as Woodruff, although Laurens had its suburban sprawl heyday back in the 80s and isn't anywhere near as bad as Woodruff. Regardless, if someone is going "to" Laurens they're going to the town in Laurens County. If they are "on" Laurens, they're on the road in Greenville.
Up in Asheville, if you are going "to" Hendersonville, you're traveling down Hendersonville to get there, at least to the point in Henderson County where Hendersonville Road becomes Asheville Highway. If you are "on" Hendersonville, you're sitting in traffic and it will take you twenty minutes at minimum to travel a quarter of a mile at peak rush hour.