Nature-based tourism (NBT) is a tourism segment that has gained popularity worldwide in recent years. NBT mostly carried out in protected areas, is seen as one of the most important tourism activities for many countries and destinations. In this study, it was aimed to quantitatively evaluate the NBT potential in three Karagöl (In Turkish Blacklake) (Borçka, Şavşat and Murgul) located in Artvin province. In the evaluation made for this purpose, CRITIC (Criteria Importance Through Inter-criteria Correlation) and PROMETHEE-GAIA (Preference Ranking Organization Method For Enrichment Evaluation-Geometrical Analysis for Interactive Aid) techniques were used. In this context, twenty-six criteria obtained from the literature and weighted by the CRITIC technique were evaluated by comparing them with the three available alternatives. In the next stage, the evaluation of the alternatives according to the weighted criteria was provided by the PROMETHEE-GAIA technique. According to the findings, the lake with the highest NBT potential in Karagöller in Artvin province was Borçka Nature Park Karagöl. The lake with the lowest potential is Murgul Karagöl, which has not yet been discovered, and its infrastructure has not been completed. It is anticipated that the results will provide practical implications for stakeholders on NBT that can be developed in the region.