As a key point of interest in its district and situated just 100 km from Paris, Sens, part of the Yonne department, is bisected by the river of the same name. This French commune made a striking entrance into history, with its inhabitants referred to as the Senonais. It's worth noting that Senonais denotes both the natural region that represents a Gallic territory of the Senones, and the Roman city of Agedincum.

During the Roman period, the banks of the Yonne river were home to a sophisticated installation for river traffic, attracting the attention of Julius Caesar's military strategists. Archaeological remains evidence the presence of an amphitheatre, a forum, and thermal baths dating back to the second century. It's believed that these baths, especially the façade, showcased various sculptures. Local dwellings of the time were adorned with mosaics.

Sens is home to 25,507 residents, but the nearby urban area houses twice as many people. The city's name originates from the Gallic people of the Senones, who were respected, even amongst the ranks of Roman cohorts. It is said that the terms 'senile' and 'senate' derive from this Gallic tribe, which settled on the coasts of the Adriatic.

At the time of Caesar's arrival, the Senonais were compelled to choose between the republic and traditional authorities. Sens holds a deep Christian tradition, with the diocese of Sens being founded around 240 AD by Saint Savinien. By the eighth century, this town became a pivotal hub for the Romanesque church. The Counts of Sens came from high-ranking lineage, connected to the royal Merovingian family. In the ninth century, the diocese of Sens held a significant place in Christian life, which effectively meant that the archbishopric of Paris was dependent on Sens, along with Auxerre, Meaux, and Orleans.

Geographically, Sens experiences a temperate climate, moderated by oceanic influences. These climatic conditions facilitated the establishment of communication routes during the Industrial Revolution. Sens is served by the TER of Burgundy, enabling easy travel to Paris, Auxerre, and Dijon. It also holds a Grand Prix and four flowers from the 2007 "Flowery Towns and Villages" contest.