At the extreme rear of Yankee Doodle is a mirror.

Peer inside the 280 square feet of historic diner space — past the 12 lonely stools and the silver skillets — and come face to face with your own reflection.

Even when the Doodle is closed, no fret: The trick works just the same. Press your nose to the window. The mirror magically transports you inside — a cozy room, a different era.

There is, in fact, only one circumstance in which the mirror can’t be seen: when a bustling Yankee Doodle crowd is blocking it.

Those moments, however, became fewer and farther between in recent years. The open hours were shortened. The Yankee Doodle that News editors used to send heelers to for hamburgers at 2 a.m. began closing earlier in the day. Gourmet Heaven and A-1, meanwhile, replaced the Doodle as a must-stop for authentic Yalies; some never experienced the fried donuts once over their four years here.

And then came yesterday. Yankee Doodle closed its doors for good.

Its final scene hardly gave any indication that something was eternally different; as usual, the electric sign shone no fluorescent light — even at 6 p.m., the peak of Eli gallivanting — and darkness reigned inside.

One difference, however, was certain. A sign on the door read “You will be missed,” signed, “-The Doodle.”

Few noticed. iPod-wielding students strolled by unaware, their sights and stomachs set on Ivy Noodle or Bulldog Burrito. It was almost as if the diner had died an Eleanor Rigby death: alone, sad.

But one by one, and always alone, students who had experienced the diner once, twice, or even regularly, stopped, shocked and, as one senior put it, “depressed.”

“This is a tradition,” he said.

YPMB members who would no longer engage in pre-game Doodling felt the loss acutely. “It was a part of us,” was all one band member could cough up.

Across the street, there was guilt.

At Au Bon Pain, a chef, Rich Gattison, mourned the loss of his favorite “egg-and-cheese” sandwich. But restaurant chains like his were at the root of the Doodle’s competition. “This is terrible,” he said.

Annette Walton, the Flower Lady, who spends her days on the intersection at which Yankee Doodle made its mark for 58 years, took the news particularly hard.

“Oh my god, oh my god. I would have given them some flowers or something if I knew. I would have given them some flowers.”

But it was what she said next that should make us think.

“New Haven,” she declared at 6:06 p.m. Tuesday night, “has got no history now.”

Or if it does, that history may soon be confined to the archives. Yale should do what it can to holster Yankee up and back onto his horse. And if that’s an impossible task, let the fall be warning: University Properties, and the rest of us, have a role to play in keeping the classic Yale neighborhood of Kingman Brewster and William Sloane Coffin’s time, of William F. Buckley and Whitney A. Griswold’s disposition, alive.

Although it may be too late.

Declared Mike Iannuzzi, owner of Tyco, in an interview Tuesday, “That era is over.”

“That era,” he clarified, of independent-owner-dominated college towns. It went riding out of town yesterday with Yankee Doodle.

And all that may be left are the reflections.