Ancient Tipasa, originally occupying only the central castle-hill, which now bears the lighthouse (see below), gradually extended over the coast-plain to the S. of the bay, and also along the slopes of the W. and E. hills. The late-Roman Town Walls, 2410 yds. in length, are still traceable at places. The busy trade of the port led, probably at an early period, to the construction of a broad Landing Place with substantial quays, the space for which was obtained by the levelling of the rocky terrace on the coast. The Roman Outer Harbour, behind the rock-islets near the E. hill, probably served as a place of refuge in stormy weather only. Since the middle ages the coast-line has been much modified by the encroachments of the sea.
We begin our walk on the N. side of the village, at the present Harbour, which occupies the site of the now submerged Roman landing-place. The huge rock (possibly used as a mausoleum), undermined by the sea, which rises in the middle of the harbour, was left untouched by the Roman engineers. During the construction of the new harbour the remains of a Roman Cistern and underground Conduits were unearthed.
From the harbour we walk to the N., round a small bay, to the Lighthouse Hill (112 ft.), gorgeous with flowers in spring, where a few vestiges of Roman streets, cisterns, and a temple are traceable (see above). At the Lighthouse (phare) we obtain a delightful view. Near it, on the N. margin of the hill, a precipice has been formed by a landslip.
The road connecting the highroad with the harbour and the lighthouse hill leads past the Hôtel du Rivage and through the *Thermæ, a grand bath-house of the 2nd or 3rd cent., rivalling the W. baths of Cherchell (p. [246]). Among the ruins, still 30 ft. high in places, extending into the Jardin Trémaux, the frigidarium on the E. side is still quite recognizable.
Near the hotel, to the left, we enter the Jardin Trémaux (adm. kindly granted), the garden of a private estate, adorned with antique and early-Christian relics. On the E. side, near the baths, we observe, protected by a roof, a fine late-Roman sarcophagus, bearing nuptial and sacrificial scenes. Near it is an old Christian sarcophagus, with Christ, the Good Shepherd (beardless); on the sides are lions tearing a gazelle to pieces.
In the middle of the grounds, to the left of the road, are a few relics of a Roman Amphitheatre (3rd cent.?), which even during the French period has served as a quarry.
The road, farther on, passes the Nymphæum (on the left), a sumptuous late-Roman fountain (3rd or 4th cent.), 26 yds. in breadth, backed with a semicircular wall. In front of it is a platform 6½ ft. high, once bedecked with Corinthian columns and with statues, over which the water descended into a narrow trough or basin.
Immediately behind the fountain is a well-preserved vault, once the Reservoir for the water brought to Tipasa by an underground conduit, 5½ M. long, from the valley of the Nador. A few paces away are the noteworthy ruins of a Roman Mausoleum (1st cent.?).
The Roman Theatre, at the exit of the gardens, to the right of the park-road, yielded the materials for building the hospital of Marengo. Several tiers of seats are still traceable.
From the W. Gate, of whose round towers alone a few relics remain, we follow the vestiges of the town-walls to the N. W. to the (5 min.) West Hill (about 100 ft.), the Râs el-Knissa (‘church promontory’) of the natives.