The Pharos lighthouse blocks — granite and limestone, scattered across the eastern harbour seabed.
The Pharos lighthouse of Alexandria — built by Sostratus of Cnidus for Ptolemy II Philadelphus between approximately 295 and 280 BCE, standing roughly one hundred and twenty metres tall and ranked among the seven wonders of the ancient world — collapsed in three successive earthquake events: the partial collapse of the lantern stage in 956 CE, the major destruction of the central shaft in the 1303 Crete earthquake, and the final destruction of the lower platform in 1480 when the Mamluk sultan Qaitbay built the modern fortress on the original lighthouse foundations using the surviving lower-platform stone. The remaining granite and limestone blocks lie scattered across the eastern harbour seabed at six to eight metres depth. Iman Hosny is the lead editor for this file.
The block field — what is on the seabed.
The eastern harbour block field covers approximately twenty-three thousand square metres of seabed in the area between the Qaitbay fortress and the harbour mouth. The institutional survey, conducted by Jean-Yves Empereur's Centre d'Études Alexandrines since the late 1960s and continuing through the 2010s, has catalogued approximately three thousand structurally significant blocks — granite columns, limestone facing stones, granodiorite statues and statue fragments, and bronze fittings. The blocks distribute into four broadly identifiable structural categories: lower-platform granite (the lighthouse's massive square base, in the largest blocks at three to five metres each), middle-shaft limestone (the octagonal middle section, in medium blocks at one to two metres), upper-shaft limestone (the circular upper section, smaller blocks at fifty to ninety centimetres), and statuary (granodiorite and granite sculpture from the lighthouse's decorative programme).
The four statue groups.
The lighthouse carried a substantial decorative programme of statuary, much of which survives on the seabed in identifiable form. The Ptolemaic colossal pair — two seated colossal statues, approximately seven metres tall, identified as Ptolemy II and his sister-wife Arsinoë II, recovered in the 1990s and now installed at the Bibliotheca Alexandrina forecourt. The seabed depressions where the statues lay are still clearly identifiable. The Greco-Egyptian sphinx group — six sphinxes, some intact some fragmentary, lying in a scattered pattern that suggests the original architectural intention was a sphinx-lined approach causeway to the lighthouse base. The lion fountain bases — four lion-shaped fountain bases, granite, from the lighthouse's decorative water-channel system that fed the harbour basins. The Ptolemaic royal procession reliefs — a group of about a dozen relief panels showing the Ptolemaic royal procession, badly fragmented but with surviving inscriptions identifying the depicted rulers.
The seasonal survey rhythm.
The block field is surveyed primarily in the spring dive season — typically March through May — when the Alexandria eastern harbour visibility is at its best (six to nine metres rather than the autumn three to five metres). The journal's ninety-two field reports across ten seasons are concentrated in the spring, with only seventeen autumn reports across the file. The institutional team's preference is also for spring work, and the journal's spring season has typically overlapped with the Centre d'Études Alexandrines' own spring survey. Tarek and Iman have logged alongside-dives with the Centre d'Études team on five occasions (2017, 2019, 2021, 2023 and 2025) with written consent from the centre's director.
The Qaitbay fortress and the reuse problem.
The Qaitbay fortress, built on the lighthouse foundations in 1480 from the lighthouse's surviving lower-platform stone, presents an unusual archaeological question. Approximately half of the visible stone in the fortress is identifiably reused lighthouse material — the diagnostic features (block dimensions, granite source, tool marks) are consistent with the lighthouse's documented construction techniques. The relationship between the eastern harbour seabed blocks and the fortress stone is therefore not a simple "blocks fell into the water" story; significant lighthouse material was deliberately moved from the seabed into the fortress during the 1480 construction, and some of the seabed blocks may have been moved back into the water during fortress repair works in later centuries. The journal's field reports flag this question where relevant; the institutional academic record discusses it at length in the Empereur publications.
What our field reports cover.
Most of the journal's reports cover the seabed condition of named blocks rather than new identifications. The Empereur catalogue is the authoritative reference for which blocks are which; our reports describe each block's current state, any visible changes from prior reports (silt cover, biological growth, mechanical damage from anchor strikes or boat traffic), the photographic condition under our calibrated standard, and any conservation observations relevant to the journal's separate conservation-protocols document. Approximately forty percent of our reports flag some form of condition concern — usually minor silt-cover changes or new biological growth — that the institutional teams use for the annual condition-tracking summary.
The companion files on Heracleion-Thonis and the broader eastern harbour survey cover the related work in the western Delta and the wider basin. The journal's methodology sets out the field-report cycle. The conservation protocols document covers the condition-monitoring questions.