This is one of few churches where choir and nave are out of axis.
This cathedral started in Romanesque style. However modifications, reconstructions and renovations, changed this. Until today the church remains in unfinished state.
Under leadership of bishop Foulques the nave is completely reconstructed in the period 1230-1240. It is 19.23 m wide and the most eastern traves of this nave can be considered the oldest.
From 1272 construction of the choir starts, which call for major modifications on the cathedral.
In 1286 the bishop dies and the plans for a huge cathedral are abandoned. However the transformations of the cathedral simply continue.
Under archbishop Jean d’Orleans (Toulouse became and archbishopric in 1317) a bell tower is constructed at the western façade during the 16th century.
In 1609, fire destroys the roof and damages the choir and the interior of the cathedral.
After this incident the choir is reconstructed with new vaults with a height of 28 m. Also in this same construction period the interior located at the choir is completely changed.
The 19th century is marked like in many other cathedrals with some thorough renovations but also some destruction. The cloister located at the north side of the cathedral and built in 12th century is demolished to construct a chapel.