"Are yous cops?" the burly man at the end of the bar asked me and my perhaps-most-uncoplike friend, a skinny, bearded archivist and indie musician.

We denied it.

"Are you wearing a wire?" asked an older guy. We assured him we were not.

Then they set aside their skepticism and bought us a round of beers. And then another round.

That's Mayfair hospitality for you. You'll find it at McGeehan's Rock Bottom — tagline: "If you're here, you've hit rock bottom" — perhaps the ultimate Northeast neighborhood bar, tucked into the basement of a rowhouse just off Cottman Avenue.

On a recent evening, we followed the steps down from the street, rang the buzzer next to the glass door (a replacement for the one shattered a few years ago on a particularly wild night), and were admitted. We found ourselves surrounded by regulars, some of whom were wearing McGeehan's sweatshirts and others of whom were McGeehans, having descended from or married into this big Irish family.

ed hille / Staff Photographer
An exterior view of McGeehan's.

McGeehan's opened in 1929, in the midst of Prohibition, as a candy shop where, according to regulars, alcohol was quietly served. ("I'm going to take the Fifth on that," said John McGeehan, reached later by phone.) The original pressed-tin ceiling remains, as does the soda counter, now covered with red, white, and blue duct tape. The walls also bear testimony to the bar's long history: branded clocks from breweries McGeehan's has outlasted, like Schmidt's and Ortlieb's; decades of fishing photos; a heartfelt, if clunky, poem about Con McGeehan, the "Mayor of Mayfair."

But McGeehan's has evolved.

"The neighborhood has changed. It's gotten more color," one regular said.

And though it was long a blue-collar, Democratic stronghold, this is a Trump bar now. I discerned this because of the Trump decal on the front door, because of the life-size presidential cutout lurking in one corner, and because my new friend Ed, an ironworker, told me so. Ed gestured with concern at the cardboard Trump, whose head was collapsing forward as though under the weight of presidential worries. "He should have his head up!" Ed said.

Then Ed bought me a beer. I selected Miller Light, which was $4 and, in keeping with McGeehan's sole marketing promise, cold.

The craft-beer and cocktail revolutions have passed McGeehan's by. But, in its favor, it's the kind of place where the bartenders will put out a crockpot or, on the night we visited, lay out a spread of soft pretzels and excellent tomato pie (Northeast insider tip: Johnny G's at Rhawn and the Boulevard).

On certain nights, only in the summertime, there is food made in-house: steak sandwiches, a shrimp scampi steak sandwich, and the legendary crabs. All of it is made by the owner, Pat McGeehan — and, then, only when the mood strikes him.

"The guy hates cooking, but he makes the best crabs," one regular told us. "You have to come back for it."

We promised we'd do just that.

McGeehan's Rock Bottom
4401 Cottman Ave., 215-624-1793

When to go: It's open, more or less, 11 a.m. to 2 a.m. daily. Go on Tuesday, Wednesday or Thursday night, "after the kids get out of Catholic school" for the summer: That's when they start serving crabs.

Bring: Anyone who can describe what neighborhood they grew up in by referencing the parish.

What to order: Ask yourself: Am I in the mood for a Miller Light, or something more exotic, like Heineken? Or keep it local with a shot of Jacquin's Rock and Rye.

Bathroom situation: Modern, single-stall restrooms are marked "Guys" and "Dolls." Being the only female in the place for most of the evening, I found the dolls' room pristine.

Sounds like: About 75 decibels of Seinfeld reruns, Flyers hockey, and neighborhood gossip.