This paper considers the role of interpretive layering, that is, combining multiple sources of interpretation in order to repeat the interpretive message, in nature-based tourism. We explore interpretive layering at an attraction (the Great Barrier Reef (GBR)) that presents several challenges to tourists and operators. The GBR, Australia, represents an extraordinary site where tourists typically have limited previous experience with the physical conditions, tourists are encouraged to shape their experience by choosing from a multitude of activities on offer, and where focused interpretive activities are more difficult due to the (underwater) nature of the attraction. Using 775 visitors surveys distributed on the return trip from the reef, we analysed the relationship between the number of interpretive types used and changes in visitors' knowledge levels, attitudes and behavioural intentions. The results highlight the important additive effects of a variety of interpretive sources on visitors' understanding of this attraction. We propose that interpretive layering may be particularly relevant to attractions that are harder to accommodate within visitors' existing frames of reference and might also be usefully applied in (post-Fordist) tourism that is characterised by a trend away from packaged mass tourism, towards products that favour flexibility, individuality, hybridity and activity.