St. Mark's Cathedral stands as one of Venice's most magnificent architectural treasures, but beneath its golden mosaics and soaring domes lies a mystery that captivated Expedition Unknown investigators. This 11th-century Byzantine masterpiece, originally built to house the relics of Saint Mark, may harbor one of history's greatest secrets - the possible resting place of Alexander the Great himself.
St. Mark's Basilica (Basilica di San Marco) is a magnificent Byzantine-style cathedral in Venice, Italy, serving as one of the city's most iconic landmarks and a masterpiece of Italo-Byzantine architecture. The cathedral was consecrated in 1094 to house the relics of Saint Mark the Evangelist, brought to Venice from Alexandria in 828 AD. The basilica features five grand domes, an ornate golden mosaic interior covering approximately 8,000 square meters, and a façade adorned with marble columns and arches. Josh Gates investigated controversial evidence suggesting that remains purported to be Saint Mark might actually be those of Alexander the Great, one of history's most sought-after archaeological mysteries.
Venetian merchants reportedly bring relics of Saint Mark from Alexandria to Venice
Construction begins on the current basilica structure to replace an earlier church
Consecration of St. Mark's Basilica
Gates investigates Alexander the Great tomb theory in Expedition Unknown
St. Mark's Basilica has been the subject of extensive historical and archaeological scholarship, with mainstream historians documenting its construction in the 11th century as a deliberate effort by Venice to establish religious and political prestige by housing the relics of Saint Mark. The transfer of these relics from Alexandria in 828 AD is well-documented in Venetian chronicles, though the exact provenance of the remains has occasionally been questioned by researchers.
The theory that Alexander the Great's body might rest in Venice rather than Saint Mark's remains is considered highly speculative by mainstream archaeologists and historians. Alexander's tomb was reportedly in Alexandria for centuries after his death in 323 BC, visited by numerous historical figures including Julius Caesar and Augustus, but its location was lost to history by the 4th century AD. No definitive archaeological or genetic evidence has connected the St. Mark's relics to Alexander, and the Venetian acquisition story, while dramatic, lacks the historical documentation that would support such an extraordinary claim.
Gates' investigation in Expedition Unknown explored this intriguing theory by examining the historical timeline of Alexander's tomb in Alexandria and the circumstances under which the Venetian merchants operated. The episode presented the case for why some researchers find the theory plausible—including the timing of the relics' removal and the confusion that might have existed in 9th-century Alexandria—while respecting that mainstream scholarship requires extraordinary evidence for such extraordinary claims. The investigation highlighted how even well-established religious relics can harbor historical mysteries that resist easy resolution.
The basilica itself remains one of Venice's most studied architectural monuments, with its mosaics, structure, and art representing a fusion of Byzantine, Islamic, and Western European influences that reflected Venice's position as a maritime crossroads. Whether the crypt contains Saint Mark, Alexander the Great, or remains of uncertain identity, the cathedral's historical and cultural significance to Venice and Christianity is unquestioned by scholars.
The bronze horses on the basilica's façade are replicas; the originals, looted from Constantinople during the Fourth Crusade in 1204, are preserved inside the basilica's museum.
The basilica served as the private chapel of the Doge of Venice until 1807, when it became Venice's cathedral.
The golden mosaics inside St. Mark's Basilica cover approximately 8,000 square meters, earning it the nickname "Chiesa d'Oro" (Church of Gold).
Napoleon Bonaparte reportedly called Piazza San Marco "the drawing room of Europe" and ordered modifications to the square during French occupation.
St. Mark's Basilica is located in Piazza San Marco in central Venice and is open to visitors year-round, though modest dress codes are enforced and large bags must be deposited at a nearby facility. Entrance to the basilica itself is free, but accessing special areas like the Pala d'Oro, the Treasury, and the museum requires paid tickets. Expect long queues during peak tourist season, and note that photography inside is generally prohibited.
The basilica is located in Venice itself; the nearest mainland city with major transportation hubs is Mestre, approximately 10 kilometers west.
Early morning or late afternoon visits help avoid the largest crowds, particularly during the peak summer months of June through August. Visiting during the off-season (November through March, excluding Christmas and Carnival) offers shorter wait times and a more contemplative atmosphere, though Venice's acqua alta (high water) can occasionally affect access to the basilica in autumn and winter.
Alexandria
Alexandria is where the relics of Saint Mark—or possibly Alexander the Great—were reportedly taken from in 828 AD, making it central to the same historical mystery.
Italy (St. Nicholas sites)
Italy has been featured in multiple Expedition Unknown investigations involving religious relics and historical mysteries, offering similar cultural and archaeological contexts.
Holy Land
The Holy Land represents another region where Gates has investigated early Christian history and relic authentication, similar to the Saint Mark investigation.
Best time to visit: Visit during early morning hours or late afternoon in spring or fall to avoid crowds and enjoy the best lighting for photography.
Travel tip: Book skip-the-line tickets in advance and dress modestly with covered shoulders and knees, as this is an active place of worship with strict dress codes.
Historical data sourced from Wikipedia