Generally speaking, it is assumed that the building we now see is that commenced by Conrad von Hochstetten in the year 1248, but more recent researches have proved that what he did was to rebuild or restore the double-apse cathedral of earlier date. The examples just quoted, however, were no other proof available, are sufficient to show that the Gothic style was hardly then introduced into Germany, and but very little understood when practised. It seems that the present building was begun about the year 1270-1275, and that the choir was completed in all essentials as we now find it by the year 1322.[75] Had the nave been completed at the same rate of progress, it would have shown a wide deviation of style, and the western front, instead of being erected according to the beautiful design preserved to us, would have been covered with stump tracery, and other vagaries of the late German school, all of which are even now observable in the part of the north-west tower actually erected. As the church is now complete according to the original design, one of its principal beauties is the uniformity of style that reigns throughout, contrasting strongly as it does with the greater number of Northern cathedrals, whose erection spreads over centuries. In dimensions it is the largest cathedral of Northern Europe; its extreme length being 468, its extreme breadth 275, and its superficies 91,464 ft., which is 20,000 ft. more than are covered by Amiens, and one-fourth more than Amiens was originally designed to cover. On comparing the eastern halves of these two from the centre of the intersection of the transept, it will be found that Cologne is an exact copy of the French cathedral, not only in general arrangement, but also in dimensions, the only difference being a few feet of extra length in the choir at Cologne, which is more than made up at Amiens by the projection of the Lady Chapel. The nave, too, at Cologne is one bay less in length. On the other hand, the German building exceeds the French by one additional bay in each transept, the two extra aisles in the nave, and the enormous substructures of the western towers. All these are decided faults of design into which no French architect would have fallen.