Continental Grand Sport Race Tire (Black) (700c / 622 ISO) (23mm) (Folding) (PureGrip)

Incredibly durable. I've ridden over all kinds of stuff, including glass, gravel, and all the crazy debris on the shoulder that comes from cars, and in the 5 years (yes, FIVE years) I've been riding these I have never once gotten a flat. (No idea how many miles because I don't use a computer or try to keep track.) I'm only replacing because the tread has worn through and sidewalls are getting crusty after all that time. I would trust these to ride over anything. They are also super fast and corner great on dry roads. Because they're pretty slick I take it easy on the turns when it's wet out. If asphalt or packed dirt/gravel is your main surface, these are a great bet.