Romanos I Lekapenos was a political usurper who became, against considerable odds, one of Byzantium's more capable rulers. He seized power as regent for the young Constantine VII, made himself co-emperor, and ruled from 920 to 944. His ambitions at Myrelaion were imperial in scale: he intended to build a palace to rival the nearby Great Palace of Constantinople — the seat of Byzantine power — and to establish a family shrine that would redefine imperial burial traditions.

The site he chose had a hidden asset. Beneath it lay a massive fifth-century rotunda, 41.8 meters in external diameter — the second largest circular structure in the ancient world after the Roman Pantheon. By Romanos's time, the rotunda was out of use. He converted it into a cistern, covering its interior with a vaulted system supported by at least 70 columns. Then, above this buried infrastructure, he built a church in the Byzantine cross-in-square form: a nine-meter-sided building with an umbrella dome, arched windows in the drum, and four side naves covered by barrel vaults.

Romanos built the Myrelaion church specifically as a burial place for his family — a private dynastic chapel of a kind that was new to Byzantine practice. In doing so, he broke with a tradition stretching back six centuries: since the time of Constantine I, Byzantine emperors had been buried in the Church of the Holy Apostles. Romanos chose a different path, one that began with his wife Theodora, buried at Myrelaion in December 922, and continued with his eldest son and co-emperor Christopher, who died in 931.

Romanos himself did not live out his reign in glory. Deposed in 944 by his own sons, he was sent to the island of Prote, where he died as a monk in June 948. His body was brought back to Myrelaion and buried in the church he had built. There is a kind of austere justice in the sequence: the man who had turned a palace into a nunnery and a cistern into a crypt ended up in the crypt himself, among the people he had loved and sometimes outmaneuvered. Later, the palace he built was indeed converted into a nunnery, as he had directed before his death.

The Myrelaion's long life was not peaceful. In 1203, during the disastrous Fourth Crusade, the shrine was ravaged by fire. The Latin occupation of Constantinople that followed (1204–1261) left the building abandoned. It was repaired after the Byzantine restoration under the Palaiologos dynasty, and the substructure — the old cistern beneath — was converted into a burial chapel.

Then came 1453, and everything changed. After the Ottoman conquest of Constantinople, the Myrelaion was converted into a mosque around the year 1500 by Grand Vizier Mesih Paşa, during the reign of Sultan Bayezid II. The building took its new name from the Turkish word bodrum — meaning subterranean vault or basement — a reference to the ancient cistern beneath. Fires damaged it again in 1784 and 1911, after which it was abandoned for decades. The modern restoration in 1986 returned it to use as a mosque. The cistern below, restored in 1990, served briefly as a shopping space before its current function: a place where women come to pray.

The Bodrum Mosque's significance is partly historical, partly typological. The Myrelaion is one of the earliest examples of the cross-in-square church plan — the form that became dominant in middle Byzantine religious architecture and spread across Orthodox Christendom. The building's nine-meter sides and umbrella dome became a template.

Constructed entirely of brick on alternating brick-and-stone foundation courses, the building features half-cylindrical exterior buttresses, an umbrella dome on a windowed drum, and barrel-vaulted side naves. Inside, four Ottoman-period piers replaced the original columns; windows, oeil-de-boeuf openings, and arches flood the space with light. A restoration in 1964–65 replaced most of the exterior masonry. The substructure — the 70-column cistern beneath — retains more of its original character: austere, massive, and dark.

Laleli is one of the older districts on Istanbul's historic peninsula, known today for its textile wholesale market, budget hotels, and position between the Grand Bazaar and Aksaray. The Bodrum Mosque opens for daily prayers. Visitors who find their way to it are sometimes surprised by how small and unassuming it looks from the outside — a brick building wedged between concrete apartment blocks. What the exterior doesn't convey is the depth: the thousand-year history layered beneath, the cistern beneath the cistern, the emperor who wanted to be buried here and was.