The possible applications of black holes are explored, with a focus on interstellar travel and energy extraction. Further to this, emphasis is placed upon Oberth manoeuvres, Hawking radiation, and the creation of black holes. An equation for the maximum $$\Delta V$$ from a one-stage Oberth manoeuvre is derived. A conclusion is reached that although these applications may be possible in the distant future, they are likely to have been superseded by more effective, viable alternatives that do not have the risks associated with black holes.