Guillaume Le Vasseur de Beauplan (1600 – 1673) was a French-Polish cartographer, engineer and architect. Here is his description of Kyiv around the year 1650: “Kiow, otherwise called Kiovia,​ was one of the ancientest cities in Europe, as may be seen still by the remains there of antiquity: as for instance, the height and breadth of its ramparts, the depth of its ditches, the ruins of churches, the old tombs of several kings found within them. Of the churches, only two remain as a memorial, which are those of S. Sophia and S. Michael: for of all the rest there is nothing left but ruins, as of that of S. Basil, whose walls are yet standing five or six feet high, with Greek inscriptions on them of above fourteen hundred years ​standing upon alabaster stones, but now almost worn out with age. Among the ruins of those churches are to be seen the tombs of several princes.
The churches of S. Sophia and S. Michael have been rebuilt after the ancient manner. That of S. Sophia makes a fine front, and looks graceful on every side, for the walls are adorn’d with several histories and Mosaick figures: which work is made of very small bits of several colours, shining like glass; and so well put together, that it is hard to discern whether it is painting or tapestry: the arch is made only with earthen pots fill’d and plaister’d all about. In this church are the tombs of several kings; and the Archimandrita or chief of all the monks resides there. S. Michael’s church is called the Golden Roof, because it is cover’d with gilt plates. The body of S. Barbara is shewn there, said to be brought thither during the wars of Nicomedia.
This ancient city is seated on a plain that is at the top of a hill, which commands all the country on the one side, and the Borysthenes (Dnieper) on the other, that river running along the foot of the hill; between which and the water stands New Kiow, a town at present but little inhabited, there being not above five or six thousand people in it. It is about four miles in length along the Borysthenes, and three miles in breadth from the Borysthenes to the hill, being inclosed with a scurvy ditch twenty-five foot wide. Its shape is triangular, encompassed with a wooden wall, and towers of the same materials. The castle stands on the ridge of a hill commanding the lower town, but commanded by Old Kiow.”
Kyiv was much more powerlful before the Mongol Invasion of 1240 than many realize. Read “Gardariki, Ukraine” e-book for more details about the city.