Building on prior findings on co-innovation and dark tourism, this research examined if and how the experiential stage (before vs. after the visit) affects the quality and the type of ideas provided by tourists. Four hundred visitors shared new ideas for a dark tourism experience, in Medellin (Colombia). Half of the sample was interviewed before visiting the site and the other half after the visit. The results show that before the visit (i.e. less information: higher cognitive flexibility and lower functional fixedness) the respondents provided more original ideas. After the visit, their ideas were rated higher in terms of feasibility and persuasiveness. Furthermore, tourists showed higher morbid curiosity before the visit, leading to morbid ideas. After the visit, curiosity about history and empathy increased, leading to educational ideas. The results can help managers to set goals for co-innovation at dark tourism sites, by considering the different experiential stages.