The Colonial Revival structure, built like a traditional Pennsylvania manor home, reopened in the spring after a nine-month renovation that preserved its limestone facade and large fireplaces.
The project is part of a $100 million rebuilding of the remaining 17 service plazas that dot the turnpike from New Jersey to the Ohio border.
The other plazas, not built to handle today's volume of traffic, are being razed and replaced with larger, more modern structures, said Carl Defebo, a Pennsylvania Turnpike Commission spokesman.
But South Midway will be preserved, the commission and HMS Host, its concession partner, agreed.
"History buffs treasure the Midway," Defebo said. "We wanted to preserve a piece of history."
The rest stop has been restored to its appearance when it greeted the first eager drivers who spilled through the tollgates in the wee hours of Oct. 1, 1940.
The interior was gutted, but its limestone facade was preserved, and inside, it has become a showcase for turnpike artifacts.
The walls are lined with black-and-white archival photos - in frames made of wood from the old building - of the construction of the turnpike and of its celebratory opening at 12:01 a.m. Oct. 1, 1940.
The dining area has a cathedral ceiling (engineers removed the second-floor dormitory, which once provided bunks for truckers) to create an airy space.
Starbucks, Sbarro, and Steak & Shake occupy space held for decades by Howard Johnson's, which operated a formal dining room and a lunch counter.
Philadelphia architecture and engineering firm Vitetta paid homage to the past by restoring the large brick-and-copper fireplaces, one of which had long ago been covered over in plaster.
The plaza was named Midway because of its location, halfway between the original end points of the turnpike at Irwin to the west and Carlisle to the east. Today, it is about three-quarters of the way to Pittsburgh from Philadelphia.
To understand the joy of turnpike travel decades ago, one need only survey the display case at the entrance. Visitors are greeted with a large display case of memorabilia: pins, pens, pennants, tea sets, decks of cards - just a portion of the 66,000 items collected by Bob and Alice Miller of New Stanton, site of an interchange, by the way, who donated their collection to the commission for public display.
A music group, the Kenny Schaffer Trio, even cut a 78-r.p.m. record dedicated to the road, "The Pennsylvania Turnpike." The record is in the case, too.
Once called "The Magic Motorway of the Future," "America's Road," and the "Forget the Weather Highway," for the seven tunnels that carried the road through the Allegheny Mountains (there are now five), the turnpike gave motorists a safer, speedier alternative to Route 30, the old Lincoln Highway, with its steep grades and frequent intersections.
Today, it is known as just the Turnpike - often derided for its annual fare hikes and regular back-ups - seamlessly flowing into the Ohio and New Jersey Turnpikes on the west and east ends of the state.
The South Midway plaza reminds travelers of the golden age of auto travel, when getting there really was the fun.
Contact Amy Worden at 717-783-2584, firstname.lastname@example.org, or follow @inkyamy on Twitter.