I-476, a.k.a. The Mid-County Expressway, a.k.a. The Blue Route, is familiar to local commuters, particularly those who have spent accumulated hours stuck in traffic.

The north-south corridor is a victim of its own success, opening in 1991 with its promise of a convenient way to navigate Delaware County north-south and south-north.

But at one time, there were two or three other color-coded routes under consideration for the county, writes Victoria Ke Li for The Philadelphia Inquirer.

The Blue Route is named after the blue-colored pencil engineers used to sketch its path when a new highway linking the western suburbs to the Pennsylvania Turnpike was contemplated back in 1956.

Had history played out differently, we could have been driving today along the Green Route.

That route would have started in Radnor where the Blue Route is today, headed west beyond Media, then back toward the current Blue Route location intersecting I-95.

A Red Route, also known as the Yellow Route, would have followed the Blue Route path but would have extended slightly east in Marple, then run parallel to the current Blue Route path.

The Blue Route was ultimately chosen because it served the most drivers with the smallest community impact.

Read more about proposed alternates to I-476, or the Blue Route, in The Philadelphia Inquirer.