What is the oldest restaurant that still exist today?

Can you tell me, if you don't mind, about the history and identity of the oldest restaurant that is still operational in our present day? I'm fascinated by the idea of a culinary institution that has stood the test of time and continues to serve its patrons with the same passion and dedication it did centuries ago. I'm curious to know what makes this particular restaurant so enduring, and what culinary treasures it may hold within its walls.