Multnomah Whiskey Library in Portland, Ore., has a lot of the things you’d expect to find in a whiskey bar — leather chairs, dark wood, a certain amber glow. It also has something you don’t see every day: a ladder.

The bartenders need those steps to reach some of the higher-perched spirits in its collection of 850 types of whiskey. Multnomah, which opened last fall, is one of a new breed of whiskey parlors that could be called “ladder bars” because they possess such an enormous variety, far beyond that of the average whiskey bar, that every square inch of wall space must be put to work.

You’ll find ladders, too, at Hard Water, a waterfront bar in San Francisco that specializes in rare and vintage whiskeys; Canon, in Seattle, where roughly two-thirds of the 3,500-bottle collection are whiskeys; the Flatiron Room, in Manhattan, which carries 750 to 1,000 whiskeys at any given time; and Jack Rose Dining Saloon, the Washington, D.C., bar that can be considered the father of the über whiskey bar. When it opened in 2011, it had 1,200 different selections. Today, it has 1,800 and room for more.

Image Erin Rose at Hard Water, which has nearly 400 whiskeys on hand. Credit... Jim Wilson/The New York Times

These saloons have timed their arrival well, as Americans’ thirst for whiskey, and for whiskey knowledge, has skyrocketed. Sales of bourbon, Tennessee whiskey and Irish whiskey, particularly high-end brands, have risen sharply over the last decade. In 2013, 18 million nine-liter cases of bourbon and Tennessee whiskey were sold in this country, compared with 13.4 million in 2003, according to the Distilled Spirits Council of the United States. Distilleries in Kentucky, Scotland, Ireland, Japan and other strongholds have responded by releasing more varieties: small batch, single barrel, barrel proof, limited edition. That’s a lot of whiskey. And obsessive bar owners are intent on cramming a good chunk of it into one space.