Some ten years later, the Long Walls were rebuilt and the restoration of the Piræus fortifications was taken in hand. Of the remains now visible, the major part belongs to this rebuilding at the beginning of the fourth century. A little less than a century had elapsed since Marathon, and we now find Athens allied with her old enemy, Persia, against another Greek state. Conon the Athenian, victorious over the Spartans in the naval battle of Cnidus, sent back Persian gold to fortify the Piræus anew, and the circuit wall, of which such extensive remains are extant, was called by his name. On issuing from the electric railroad station, the visitor sees before him, a few yards distant, the Great Harbour’s smaller, inner fold, known in antiquity as “The Marsh” (Port d’Halæ) or, perhaps, as the “Blind” Harbour. This inner harbour, roughly a third of a mile by a sixth in size, now furnishes ample accommodation for smaller craft and a convenient landing-place, although in Conon’s day it was probably more of a marshy barrier than a navigable sheet of water. If the whole contour of the two harbours together suggested the designation of “Cantharus,” it may have been from either the meaning “Beetle,” or that of “Two-handled Cup.” Until recently, the name was identified with the southernmost portion only of the Great Harbour. The _locus classicus_ is the “Peace” of Aristophanes. Dædalus and Icarus with their flying-machines had long since anticipated the modern aëroplane, and in this comedy Trygæus in search of Peace starts out to navigate Zeus’s ether on his “beetle.” Then, as now, a safe landing-place for the airship was a desideratum, and Trygæus states that he will have as a safe mooring “the Cantharus harbour in Piræus.”[4] Footnote 4: The Cantharus, or beetle, of Trygæus is likened in the comedy to a Naxian boat, a resemblance easily recognized in the drinking-cup called “Cantharus,” with its two projecting handles for bow and stern. Skirting now the northern margin of the inner harbour, the route will follow in part the probable line of the demolished wall of Themistocles, which extended on and reached the water outside both the peninsula of Eetioneia and the outer bay of Krommydaru, where traces of the more ancient fortifications are still extant. Close by the modern station of the Larisa railway, however, will be found the very considerable ruins of a gateway identified with the Conon walls. This alone is an ample reward for the long détour around the harbour.