Dark tourism is defined as the act of tourists traveling to sites of death, tragedy, and suffering (Foley and Lennon, 1996).

Dark tourism theory, formally known as Thanatourism, explores the human fascination with visiting sites associated with death, tragedy, suffering, or the macabre. The theory suggests that travelers are drawn to these locations—ranging from the Auschwitz-Birkenau concentration camp to the Chernobyl Exclusion Zone or Ground Zero in New York—not out of a morbid desire for ghouls, but for a complex mix of educational, memorial, and psychological reasons. Academics like Malcolm Foley and J. John Lennon, who coined the term in 1996, argue that dark tourism provides a "safe" way for people to confront the reality of mortality and the darker side of human history. The theory also examines the "spectrum" of dark tourism, ranging from "darkest" sites (sites of actual death with a focus on education) to "lighter" sites (simulated tragedies or entertainment-focused attractions like London Dungeons). A major part of the theory today involves the ethics of commodification: whether turning a site of tragedy into a tourist attraction is a way to "never forget" or a disrespectful way for corporations to profit from human suffering.