The Manhattan Cocktail is an old favorite in my family, maybe in part because my parents grew up in New York City and I and most of my 5 siblings were born there. or maybe it's just a great drink.
The classic Manhattan is made from rye whiskey with sweet vermouth and a dash of bitters, and it is always garnished with a cocktail cherry. (I wonder if the sweet, lurid Maraschino cherry would ever have caught on as a garnish had the Manhattan not pulled it into fame on its coat-tails.)
Today many people and bars make a Manhattan with Bourbon instead of rye whiskey. In my mind this is a mistake; the drink is sweet enough without the added unctuousness of a rich Bourbon whisky. If I have no rye and I must make a Manhattan, I add an extra dash of bitters and think of it as more on the Wall Street end of the island.
For a special experience, try it with Red Dubonnet.
Better yet, try the elusive Carpano Antica sweet vermouth, if you can find it. I have found it in the North End and at some Luke's Liquor Stores, and I saw it a few times at the NH State Liquor Stores. Carpano Antica is expensive, and it is not for everyone; it is a complex potion, with distinct notes of vanilla. If you find it does not make the Manhattan that you enjoy, try it on the rocks with a twist of orange zest.