Katič and Sveta Neđelja are two small islets on the Adriatic Sea, located opposite of the town of Petrovac in the Montenegrin municipality of Budva.
The Sveta Neđelja islet has a small church of the same name built upon it, and coupled with the Katič islet, makes an attraction for diving enthusiasts.
Wikipedia https://en.wikipedia.org/wiki/Sveta_Neđelja
Coordinates 42°11'53.308" N 18°56'10.969" E