From 1517 until his death in 1519, Leonardo Da Vinci lived in Amboise, France as a guest of King Francis I.  Sketches for a royal palace in Romorantin are found in Da Vinci’s Codex Atlanticus. In these sketches, he outlines a plan for a new town at Romorantin. The overall concept of Da Vinci’s design was centered around incorporating the existing royal buildings in the town into a new network of gardens and chateaus. His plan included a canal system to adequately drain the area and prevent flooding that plagued the area due to the Saudre River. King Francis I financed this portion of the project in 1518, but he ultimately decided not to pursue the construction of the Romorantin. He decided to build a chateau in Chambord instead, so Da Vinci’s designs for the Romorantin Palace were never constructed.

Sources:

Pedretti, Carlo. “Leonardo Da Vinci: The Royal Palace at ...” Abebooks.com, Belknap Press of Harvard University Press, 1 Jan. 1972, www.abebooks.com/Leonardo-Vinci-Royal-Palace-Romorantin-Pedretti/9101029....

Tanaka, Hidemichi. “Leonardo Da Vinci, Architect of Chambord?” IRSA, vol. 13, no. 25, 1992, www.jstor.org/stable/pdf/1483458.pdf?acceptTC=true&coverpage=false.