  Citation: Pérez Garrido, B.; Sebrek, S.S.; Semenova, V.; Bal, D.; Michalkó, G. Addressing the Phenomenon of Overtourism in Budapest from Multiple Angles Using Unconventional Methodologies and Data. Sustainability 2022, 14, 2268. https://doi.org/10.3390/su14042268 Academic Editor: Chia-Lin Chang Received: 29 January 2022 Accepted: 15 February 2022 Published: 16 February 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). sustainability Article Addressing the Phenomenon of Overtourism in Budapest from Multiple Angles Using Unconventional Methodologies and Data Betsabé Pérez Garrido 1, * , Szabolcs Szilárd Sebrek 2 , Viktoriia Semenova 3 , Damla Bal 3 and Gábor Michalkó 4,5 1 Department of Computer Science, Institute of Information Technology, Corvinus University of Budapest, 1093 Budapest, Hungary 2 Corvinus Institute for Advanced Studies, Corvinus University of Budapest, 1093 Budapest, Hungary; sebrek@uni-corvinus.hu 3 Doctoral School of Business and Management, Corvinus University of Budapest, 1093 Budapest, Hungary; viktoriia.semenova@stud.uni-corvinus.hu (V.S.); damla.bal@stud.uni-corvinus.hu (D.B.) 4 Institute of Marketing, Corvinus University of Budapest, 1093 Budapest, Hungary; gabor.michalko@uni-corvinus.hu 5 CSFK Geographical Institute, 1112 Budapest, Hungary * Correspondence: perez.betsabe@uni-corvinus.hu; Tel.: +36-1482-7478 Abstract: This paper addresses the phenomenon of overtourism in Budapest from multiple perspec- tives, starting with an overview that uses information collected from news, media, and academic tourism literature. Further, the phenomenon of overtourism is addressed quantitatively using differ- ent indicators, including tourism density and intensity. According to these indicators, the center of Budapest (formed by districts I, V, VI, VII, VIII, and IX) has been strongly affected by the presence of tourists, while districts physically far from the center have been less affected. This fact suggests the heterogeneity of the city in terms of overtourism. The number one catalyst of the negative impacts of foreign visitors’ behavior is party tourism (‘ruin pub’ tourism), which involves an unconventional use of the Hungarian capital. Finally, using an unconventional optimization method called fuzzy linear programming, we attempt to explore the challenging problem of identifying the optimal number of tourists for the city. The results of the study have important theoretical, methodological, and practical implications. On the theoretical side, we offer a comprehensive understanding of the phenomenon of overtourism in Budapest. Methodologically, the integrated approach in terms of data gathering and unconventional analytical methodologies (comprised of a case study analysis, the assessment of effective indicators for measuring the discussed phenomenon, and the demonstration of the sustainable number of visitors) represents a novel perspective about the extent of overtourism in Budapest. On the practical side, our findings provide valuable guidance for policymakers to help mitigate the problem of overtourism in the city. With regard to future research, we suggest extending and updating the results presented in this study to develop more sustainable tourism strategies. Keywords: overtourism; Budapest; tourism carrying capacity; unconventional data gathering; unconventional analytical methodology 1. Introduction In 2019, Budapest was named the best destination in Europe, outranking classic urban destinations such as Paris, London, and Barcelona [1]. Within the same calendar year, the capital of Hungary ranked second on the “Best in Travel 2020” list, being awarded the title of the world’s most affordable large city [2]. Indeed, the year 2019 witnessed unprecedented tourist traffic in Budapest and the Hungarian tourism sector enjoyed “a golden age” [3] before the COVID-19 pandemic. The contribution of tourism to GDP reached 13.2% in 2019 and the growth rate of the tourism sector exceeded both the EU and worldwide average [4]. Being among the most popular tourist destinations, however, has its downsides. Earlier, Budapest was ranked fifth among the European cities most affected by overtourism in Sustainability 2022, 14, 2268. https://doi.org/10.3390/su14042268 https://www.mdpi.com/journal/sustainability