The Shake Shack burger joint in Harvard Square opened at 11 a.m. today – after a few days’ soft opening in which it sold only desserts – with frozen custard mix-ins called “concretes” customized with Cambridge flavors on what was forecast to be one of the coldest, snowiest days of the fall and winter.

But it also opened with a second-floor fireplace, which would make it immediately appealing on even a day forecast to be one of the coldest, snowiest days of the fall and winter.

The fireplace wasn’t lit in its opening hours, but its existence puts it in all too rare company even in such a cold, snowy climate, and a day expected to accumulate even 3 to 5 inches of snowfall also provides an excuse to show off some of Cambridge’s coziest eateries. (Two and a half of which, are you’ll see below, are on a single short street in Harvard Square.)

Click the purple summary boxes for a map to the restaurant. And let us know about other Cambridge restaurants with fireplaces we missed and Somerville restaurants that could be added.

Shake Shack, Harvard Square

First, Shake Shack itself. It takes over 92 Winthrop St., once the Om restaurant and nightclub, and becomes the second Massachusetts location for the chain after a Chestnut Hill site that opened in March. It seats 108 and will likely fill up fast and frequently with people demanding its “modern-day ‘roadside’ burger stand” fare, which Chief Executive Randy Garutti has described to The Harvard Crimson as being less fast food, “more fine-fast or fine-casual.”

Burgers cost from $4.85 to $8.95, fries are $2.85 and the dessert drinks range from $4.25 to more than $6.60. There are also hot dogs, beer and wine and various other items on the menu.

Open 11 a.m. to 11 p.m. daily, the location has even some rare and unique items in addition to the fireplace. It will serve the chain’s skin-on, Idaho Russet potato “fresh fries,” available at a few locations, that are hand-cut daily and cooked twice; and there are custom concretes paying homage to Harvard University (the Crimson Red Velvet, with vanilla frozen custard blended with a slice of crimson red velvet cake) and the Massachusetts Institute of Technology (MInT Chocolate, with chocolate frozen custard blended with minted marshmallow sauce and chocolate truffle cookie dough) as well as one borrowed from the Chestnut Hill Shack, Lobstah Shell (vanilla frozen custard blended with a “lobster tail” pastry shell, strawberry purée and ricotta cream).

Five percent of sales from the Lobstah Shell concrete will benefit Cambridge’s Youth on Fire nonprofit helping homeless youth, and Shake Shack team members will volunteer at events run by the organization, the company said in a Tuesday press release.

In addition, through the end of January, there will be a Hasty Pudding Milkshake (vanilla frozen custard hand-spun with banana and salted caramel sauce) in honor of Harvard theater group The Hasty Pudding Institute of 1770 taking over the nearby Tommy Doyle’s pub and restaurant at 96 Winthrop St.

“Cambridge is absolutely amazing with its vibrant food culture, energized college scene, wealth of history and central location,” Garutti said in the release. “We’re excited to further our commitment to Boston and deepen our relationship with the local community.”

The Red House, Harvard Square

If your goal is to eat by an actual roaring fireplace, The Red House is probably where you want to be. It’s likely the closest you’ll come to the classic image of eating in a classic American kitchen by a big fireplace radiating heat from large pieces of slowly charcoaling firewood. This is homey for a good reason – the restaurant is in a house built in 1802 and used as a home for the next two centuries.

Zagat calls Red House food “hearty” yet “sophisticated” and says it’s “fancy” yet fairly priced, starting with chowders and salads from $8 to $13, pasta and entrees served at two sizes from $14 to $25 and a specialty lobster menu offering six dishes from $16 to $29, including a Lobster Three Ways! with spicy jalapeño lobster taco, grilled lobster tail and crispy lobster cake.

Bondir, Area IV

Food writer Corby Kummer sums up Bondir as “unpretentious, fresh and local,” and there’s not much else to say about this cozy, farmhouse-style restaurant with 28 seats and small fireplace salon. Diners gush over what chef Jason Bond makes from the “vegetables picked the same day, fish hours out of the ocean, pasture-raised meats” touted on the website, which showcases and archives the ever-changing menus – lately offering everything from Blue Corn Grits to Slow Roasted Duroc Pork Shoulder with squash and sauerkraut. Food lovers have celebrated Bondir’s offering of every course as half portions, advising three half portions per diner, and prices on the latest menus are split into simple tiers, starting with $16 appetizers, $18 and $29 meals and $12 desserts.

Ah, there may be one more thing to say about Bondir: Boston Globe reviewer Devra First called the restaurant “thoughtful” in a 2011 review with this appealing anecdote:

It’s the end of a wonderful meal, and the staff at Bondir is tiptoeing past our table, arms full of woolens. They stop in front of the fireplace, where they unfurl our coats, holding them before the flames until the garments are toasty. It’s a cold night we’re heading into. They want us to take some of the restaurant’s warmth with us.

But as you’ll see in the photo above by Yelp reviewer T.F., a diner’s full meal won’t be in front of that fireplace.

Christopher’s, Porter Square

The website for this classic, comfortable restaurant, with its sprawling, eclectic menu and diverse selection of beers, quotes Boston magazine as saying it has “the biggest, most blazing fireplace anywhere in the commonwealth,” but that must have been a while back. Let’s just say it’s easier to find that quote via Christopher’s than via the magazine itself, and the fire is not as blazing as the quote might suggest – the flames are modest and so is the warmth coming from them, but it’s a for-real fireplace and a delight to have and sit near. Why would anyone sit anywhere else?

Vegetarians will be as happy with the Christopher’s menu as meat eaters, with each having their own great burger (one an award-winning veggie burger) and a staggering variety of other foods to choose from, starting with more than a dozen appetizers, eight salads and even four kinds of nachos. You can start eating at as low as $3.95 for soups, and about the most expensive dish you can order is $14.95.

Catalyst, Kendall Square

Modern American restaurant Catalyst opened in September 2011 with a few items contributing mightily to the buzz – including a flexible floor plan catering to business meetings for Kendall Square startups and venture capitalists; 30-foot windows; and a two-way fireplace.

Most talk about the restaurant has been praise for chef William Kovel’s cuisine, with a frequently changing menu that has soups now at $9, starters from $9 to $14, sides $6 to $10, pastas splittable at $11 or $22 and entrees from $15 (the burger) to $29 for scallops, Tournedos of Beef or Rohan Duck Breast.

Zagat calls it a fine-dining “standout” and “sublime,” with some saying

“the best part” is the “airy,” “trendy” setting, featuring a fireplace lounge and patio.

Or, as Tracey at the 40-Something Life blog describes it, “a loungey, retro casual area in front of a large blue flame gas fire that if it didn’t look so cool, it would be cheesy.”

The Black Sheep, Kendall Square

This restaurant, tucked away in the former firehouse that is The Kendall Hotel, predates the new wave of high cuisine that has transformed the square – and that’s a bit unfair. The Black Sheep (so named because the firehouse that was once here was reputed to be the black sheep among Cambridge firefighting brigades), like the new guys, uses organic and locally grown produce and has its a menu with its share of innovative American home-style cooking, as well as some key vegetarian and vegan dishes. Certainly dinner prices are indicative of a fine-dining experience, with starters from $10 to $14, soups and salads from $7 to $10 and entrees from $16 (the veggie burger) to $31 (the filet mignon).

And, of course, it has that wood-burning fireplace, as a proper Victorian should.

Honorable mention: Grendel’s Den, Harvard Square

This American-fare, vegetarian-friendly restaurant and bar has been around since 1971, charming visitors with its cheap, flavorful grub and fireplace. Well, faux fireplace. It casts heat – but if you’re looking for the real thing, this humble device might not be enough for you.