The architecture of its eastern end forms a triconch or trefoil plan, consisting of three apses around the crossing, similar to that at St. Maria im Kapitol.

The Cologne text Aedidius Gelenius, a catalogue of local saints, mentions in the 1645 edition a possible origin for the church in pre-Carolingian times.

The Chronicon provides an unbroken history of the abbey and the events leading to its partial destruction by Saxons in 778, while Charlemagne was fighting in Spain.

[1] Writing in 1900, Otto Opperman, a scholar in Germany, proved that this chronicle is a false history, concocted by Oliver Legipont, a Benedictine Monk residing at Great St. Martin’s in 1730.

[2] Other theories, including one that suggests the Church was built in Frankish times (during the 5th to 9th centuries) are similarly unsupported by evidence and likely apocryphal.

The Lorsch Codex, which provides a more trustworthy source of information, mentions the founding of the church by the Bruno the Great (953-965) as a men’s choir house in honor of Martin of Tours.

The abbey at the site of Great St. Martin was caught in the conflagration, and although the specific damages are not known, it is supposed that the entire Church was destroyed.

The Archbishop of Cologne Philipp I. von Heinsberg sanctified the new building in 1172, and the first phase of construction, the tri-apsidal structure was built, with three round apses meeting in the shape of a cross.

The abbot’s brother bequeathed in his final will money towards the purchase of new stone for the abbey, indicating some construction was ongoing.

Reforms under abbots Jakob von Wachendorp (1439–1454) and Adam Meyer (1454–1499) provided a stronger financial footing for the Benedictine abbey.

Also during this period, the interior of Great St. Martin was decorated with medieval altars, which would later be replaced with newer furnishings in the 17th century.

In 1707, the decaying interior walls of Great Saint Martin were repaired and refurbished, remaining faithful to the previous design of the Church.

Abbott Franz Spix, overseeing the abbey in 1741-1759, raised the area of the altar and laid it further back in the apse.

[8] Around forty years later, at the end of the 18th century, Ferdinand Franz Wallraf saw that the Church was embellished with new adornments appropriate to the style of the age.

These changes caused controversy with the 19th-century Catholic renewal movement, who said that these parts of the Church’s adornment should be removed, on the grounds that they were too pagan in theme.

This occupation put a definite end to the medieval traditions of the city, and began a strong anti-clerical movement in its place.

The monastery at Great Saint Martin was disbanded in 1802, and the remaining 21 monks were obliged to find other places to live.

Four years later, the building of the two missing towers was begun, initiated by Heinrich Nagelschmidt, who also created a plan for the full restoration of the church.

In 1875, Great Saint Martin received a new roof, newly built western gables, a new window in the south wall, and finally, the completion of its two missing towers.

August Essenwein, director of the Germanic Museum in Nurnberg, was entrusted with this task, and sought to return the decorative elements to authentic medieval designs.

[11] The only remaining major changes to the building in the 19th century occurred in 1892, when the east side of the Basilica was renovated to better show the cloverleaf design of the choir.

The altar was consecrated by Archbishop Joseph Höffner, who installed holy relics of Brigitta von Schweden, Sebastianus and Engelbert of Cologne, in its sepulchre.

As of 2009, Great Saint Martin Church is being used by a branch of the Monastic Fraternities of Jerusalem and is open for visits again.

The location of these buildings, directly on the banks of the Rhine, as well as their structure, indicates use as storage, for market goods shipped along the river.