There is no cocktail quite as classic as a good old fashioned, as you can guess by the name. This concoction dates back several centuries to English apothecaries, and today's more Americanized old fashioned typically consists of whiskey, a sugar cube, bitters, and water, plus a certain cocktail glass that's suited for this drink.

An old fashioned is typically served in a rocks glass, which is the best fit because of its solid, weighty bottom that can stand up to the muddling together of the sugar and bitters. The old fashioned is practically defined by this glass — a relationship that goes the other way as well, since a rocks glass is often called an old fashioned glass.

Notably, many whiskey cocktails are traditionally served straight up in a small shot glass, and were designed to be consumed in one gulp. Meanwhile, the old fashioned is designed to be sipped slowly, since it's a more of a thinking and savoring cocktail, making a 4-to-10 ounce elegant rocks glass a much better fit.