Broken Fang Cave

Broken Fang Cave is a cave located west of Whiterun, south east of Rorikstead and south of Morthal. It is a home to vampires. The cavern itself is far from Whiterun but is an excellent place to acquire Sanguinare Vampiris and turn into a vampire at low levels. It is also a location for a Companion's radiant quest. Acquiring Sanguinare Vampiris and turning into a vampire will however be pointless if you decide to pursue the Companion's questline for later on the story, they turn you into a werewolf and cure you of your vampirism, thus barring you from becoming a vampire again.

Side Note: This is an excellent location to collect Vampire Dust for use in Invisibility Potions. Also, if you wish to become a vampire, this is a great place to become one. You can contract the disease by being attacked by a vampire, try turning down the difficulty in the settings and allow them to attack you while you continuously heal. A message will appear when you contract it, you will have 72 hours (3 days) to cure the disease before it becomes permanent.