The road circling Mount Pion was the main road through the city and also accepted as the holy road or Sacred Way of Ephesus. The section of the road between Celsus Library and the Commercial Agora was covered with marble plates. The original construction dates to the 1st century AD, though it was rebuilt in the 5th century AD.

The paved section of the Sacred Way would have been used by carriages only. Traces of chariots can still be seen here along the road. As the main road through the city it would have been heavily trafficked and the marble road was repaired several times throughout the centuries. The western side of the Sacred Way was enclosed by the Commercial Agora. Visitors today can still see the remains of the columns standing on a base-wall of 1.7 meters high. This wall was built as a pedestrian walk-way during the reign of  Nero, along with a series of stairs both on the north and the south ends of the Agora.

Busts and statues of the important people of the time would have been erected along the road, and letters from the emperor would have been carved into the blocks of the road for people to read. One of the most famous carvings along this road is believed to be an advertisement for the Brothel. This would be the first advertisement in history. The block is a carving of a left footprint, a purse of money, a woman, a heart, and a library. This has been interpreted as saying that a visitor could continue walking that way to find a bordello on the left side of the street. Anyone whose foot was smaller than the one on the pavement would have been declared underage and denied entry. The woman and the heart are said to mean that beautiful women are waiting at that building and eager for affection. The coin-purse tells visitors their affection can be purchased, but if you’re out of money at least the library is nearby.