Pausanias Description of Greece 6.23.8

[8]
  The way from the gymnasium to the baths passes through the Street of Silence and beside the sanctuary of Artemis Philomeirax. The goddess is so surnamed because she is neighbor to the gymnasium; the street received, they say, the name of Silence for the following reason. Men of the army of Oxylus were sent to spy out what was happening in Elis . On the way they exhorted each other, when they should be near the wall, themselves to keep a strict silence, but to listen attentively if perchance they might learn aught from the people in the town. These men by this street reached the town unobserved, and after hearing all they wished they went back again to the Aetolians. So the street received its name from the silence of the spies.

[8] The way from the gymnasium to the baths passes through the Street of Silence and beside the sanctuary of Artemis Philomeirax. The goddess is so surnamed because she is neighbor to the gymnasium; the street received, they say, the name of Silence for the following reason. Men of the army of Oxylos were sent to spy out what was happening in Elis. On the way, they exhorted each other, when they should be near the wall, themselves to keep a strict silence, but to listen attentively if perchance they might learn something from the people in the town. These men by this street reached the town unobserved, and after hearing all they wished, they went back again to the Aetolians. So the street received its name from the silence of the spies.