The Greyhound is a two-part classic that you can make as quickly as the drink's namesake canine runs. Composed of gin or vodka and grapefruit juice, this cocktails is simple, tart and refreshing—just what you need on a warm day or whenever you're drinking before noon. The Greyhound's first known mention arrived thanks to bartender and author Harry Craddock's “Savoy Cocktail Book,” a classic tome that was published in 1930. In his book, Craddock instructed readers to make the no-frills Greyhound with gin, grapefruit and ice. Once vodka appeared in the United States and started to gain traction circa 1950, the spirit increasingly began to replace gin in the cocktail. The Greyhound bus terminal's ubiquitous restaurant chain, Post House, served their version with vodka. And since the restaurants were frequented by travelers all over the country, the vodka-spiked drink propagated widely. Today, it's common to see both spirits employed in the Greyhound, so try both and see which one you prefer. But be sure to choose a high-quality base spirit. With only two ingredients, there's nowhere for a subpar vodka or gin to hide. The same goes for the juice. Over the decades, many bars have used canned grapefruit juice in their Greyhounds. This is an option, of course, but fresh juice gives the drink a more refreshing kick. Similar to how a Screwdriver just tastes better with fresh OJ, using fresh grapefruit in the Greyhound results in a cocktail that is perfect for breakfast, brunch and midday pick-me-ups. Fortunately, one grapefruit yields a lot of juice, so you often only need one to make the cocktail. Looking to throw a bone between the citrus and spirit? Add salt to the rim, and you have another canine-related classic, the Salty Dog. This simple variation can also be made with either gin or vodka, and the salted rim lends a savory quality to each electrolyte-laced sip. 10 Grapefruit Cocktails to Try Right Now