What do the blue shaded lines indicate throughout a sectional excerpt?

The blue shaded lines on a sectional chart indicate Victor airways, which are designated routes for aircraft in the en-route portion of flight, specifically within controlled airspace. These airways are used primarily for navigation by aircraft flying under instrument flight rules (IFR).

Victor airways are typically established between ground navigation aids such as VORs (VHF Omnidirectional Range stations) and are depicted as blue lines connecting these navigational points. They facilitate efficient and organized air traffic flow, allowing pilots to navigate safely along predetermined flight paths. Understanding these airways is crucial for remote pilots, especially when operating in more congested airspace where adherence to these routes is essential for maintaining safety and compliance with regulations.