Aden is a seaport city in Yemen located in the Gulf of the same name by the Red Sea.
History
Nick Fury, on route to a military conference, wanted to check the status of one of his S.E.A.L. teams, on a mission to stop a Ten Rings freighter in the seaport city of Aden in Yemen.
While the team leader was updating Fury, Iron Man attacked the freighter and the Ten Rings operatives inside, saving the S.H.I.E.L.D. operatives when they got surrounded. The team leader tried to question Stark, but he flew away before being able to do so.
Stark recorded the entire conversation and listened to them in his home to know more about Fury's intentions with him.[1]
Tony Stark returned to Yemen during his early quest of establishing world peace, using his newly created identity as Iron Man. Stark arrived at a ship attacked by Somali pirates, and while J.A.R.V.I.S. was cross-checking the information with the International Maritime Bureau, Stark recognized their identity as Somali pirates, and attacked them in retaliation.[2]