<p>Tourism plays a vital role in the global economy, serving as a crucial foreign exchange earner for developing countries and the world's poorest nations. This study focused on Ondo State, Nigeria, where we calculated the human physio-climatic index and identified significant tourist attraction sites with the aid of GPS meter during fieldwork conducted in 2023 for the study. The data used in this study were obtained from the Agroclimatological and Ecological Monitoring Unit in Akure, Ondo State, Nigeria, covering the period from 2011 to 2021. The data were collected from weather stations located in various Local Government Areas of Ondo State, where the selected tourist sites are situated. The study utilized daily measurements and observations of air temperature, air relative humidity, wind speed, and solar radiation from various weather stations in the study area to calculate the Physiologically Equivalent Temperature (PET) using the RayMan model. The resulting monthly PET values and tourist attraction sites were mapped using ArcGIS Pro 2.0, providing a visual representation of the tourism-bioclimate relationship. Four classes of PET, such as; no thermal stress (23.1 ℃ to 27.0 ℃), slight heat stress (27.1 ℃ to 31.0 ℃), moderate heat stress (31.1 ℃ to 36.0 ℃), and strong heat stress (36.1 ℃ to 42.0 ℃) were identified. Fieldwork conducted for this study identified 8 significant tourist attraction sites in Ondo State, Nigeria, such as; Cave of Ashes, Coast Creek and Canal, Ebomi Lake (Mysterious Lake), Idanre Hill, Igbo Irunmole and Igbo Olodumare (The Forest of the Almighty), Oke Maria, Owo Museum of Antiquities, and Palace of the Deji of Akure. The thermal condition information obtained from this study is essential for authorities responsible for health, tourism, and recreation, providing valuable insights for decision-making and planning. This study is crucial for decision and policy makers in Nigeria, as it highlights the potential of tourism as a new frontier for economic growth and development. By understanding the impact of weather and climate on tourism, policymakers can make informed decisions to promote sustainable tourism practices and mitigate the effects of climate change. The study's focus on the sensitivity of weather conditions and climate variability to the tourism industry is particularly relevant in today's era of global climate change. By addressing international goals related to climate change and sustainable development (SDGs), the study provides valuable insights for policymakers to develop strategies that balance economic growth with environmental sustainability. Policymakers can use the study's findings to develop sustainable tourism strategies that take into account the impacts of climate change. Foresights of this study can also bring policies aimed at reducing greenhouse gas emissions and adapting to the effects of climate change. By promoting sustainable tourism practices, policymakers can create new economic opportunities and stimulate growth in local communities. Overall, this study provides critical information for decision and policy makers in Nigeria, enabling them to develop strategies that promote sustainable tourism development, mitigate the effects of climate change, and drive economic growth.</p>