For the Thriasian Plain’s residents, the Eleusinian Cephissus was both a lifeline and a bane. Currently mostly dry, in ancient times it was a robust river fed by streams from western Mount Parnitha and eastern Cithaeron. Winter often saw it overflowing, ravaging fields and properties near Eleusis. Demosthenes, the Athenian orator, highlighted it as a notably destructive waterway, prone to flooding farms after heavy rains.
This unpredictability also posed challenges for travellers and mystai (initiates). Those journeying to Demeter’s sanctuary had to ford the river about a kilometre east of Eleusis. Normally, the river’s usually shallow waters posed little trouble, but heavy rains or floods made the crossing perilous. Pausanias labelled this river as more turbulent than its Athenian counterpart. In the late 4th century BCE, Xenokles erected a stone bridge to aid pilgrims and Eleusis locals. However, this bridge was eventually replaced by a temporary wooden or stone construction.
During his 124 or 125 CE Athens visit and initiation into the Eleusinian Mysteries, Roman Emperor Hadrian witnessed a devastating flood. In response, he ordered the river’s embankment and funded a new 50-metre-long stone bridge. This structure, supported by four sturdy, low arches with deep-set piers and semi-cylindrical buttresses, was built to withstand the strong current. Large, rectangular stone blocks from Piraeus were placed in the riverbed to prevent the foundations’ erosion. Similar to the Athenian Cephissus bridge, Hadrian’s bridge might have been a site for the “gephyrismoi” rituals.
The bridge remained functional for centuries, continuing to serve travellers to Megara, Thebes, and Corinth, even as the Demeter sanctuary’s importance waned and the Mysteries ceased. A Byzantine-era rectangular tower was later added for road control. Over time, the river altered its course, burying the bridge under soil. While Gustave Flaubert didn’t observe the bridge, he noted an “ancient well” nearby, characterised by green stones and abundant water.
In the 1950s, architect and archaeologist Ioannis Travlos undertook the excavation of the ancient stone bridge. Within the Byzantine tower’s wall, he discovered a late 3rd century BCE Pentelic marble inscription. This inscription, linked to a family tomb, listed six individuals, five of whom were from the ancient deme Kopros, believed to be situated between Thria to the east and Eleusis to the west. Kopros, a small coastal deme, might have originally been an island formed from sediment deposited by the Cephissus, now connected to the mainland.
Pausanias recorded two local legends about the Eleusinian Cephissus. The first involves a spot by the river named Erineus, where Pluto was said to have entered the Underworld with Persephone. This story likely stems from a reference in the Homeric Hymn to Demeter, which describes a coastal plain near a flower-filled meadow where Persephone and Oceanus’s daughters were playing.
The second legend details the heroic deeds of Theseus, the mythical Athenian figure, who vanquished the notorious robber Polypemon, also known as Procrustes, near Cephissus. This villain forced travellers to fit an iron bed; he either amputated their limbs if they were too long or stretched them if too short, leading to their death. Theseus turned the tables on Procrustes, forcing him onto the bed and severing his overhanging limbs.
