This dissertation examines the effect of podcast tours on park visitor experiences. Podcast tours have emerged as a new medium in facilitating the interaction between tourists and destinations. Providing visitors with enhanced experiences through the use of interpretive technologies is especially important for national parks dealing with enhancing visitors' experiences which may influence visitors' perception of environmental stewardship and, in turn, positively affect preserving environmental resources. Furthermore, there has been a noticeable increase in consumer demand for podcast tours. Based on theoretical accounts that human voices convey rich social information, this dissertation proposes that podcast tours enhance perceived social presence and mindfulness which leads to enhanced tourist experiences (learning, enjoyment, and escape) and environmental stewardship (attitudinal and behavioral stewardship). A field experiment was conducted at Padre Island National Seashore using MP3 players containing podcast tours. The podcasts were manipulated using four experimental conditions: 2 information source compositions (single narrator voice vs. multiple narrator voices) x 2 narrating styles (formal style vs. conversational style). The questionnaire administered to subjects after they took the podcast tour included measures of social presence, mindfulness, tourist experience (learning, enjoyment, and escape), and stewardship (attitudinal and behavioral stewardship). The pre-questionnaire included question items regarding the nature of the visit, visitor characteristics, technology usage behavior, audio tour evaluation and socio-demographics. Responses from 221 visitors were analyzed using structural equation modeling with LISREL 8.7. The results provide evidence that multiple voices, and to some extent also narration style, positively increase social presence but neither experimental condition had any influence on mindfulness. The increased feeling of social presence influences park visitors' enjoyment and escape experiences but not learning. Mindfulness was found to affect visitors' learning, enjoyment, and escape experience. The results further show that enhanced experiences positively influence attitudinal stewardship which in turn leads to behavioral stewardship toward national parks. The results of this dissertation generally support the theoretical model suggesting that even if communicated through audio-only media, the human voice creates and sustains a positive social context for meaningful interaction which influences tourist experiences and stewardship. Mindfulness was also found to be an important construct impacting the quality of visitor experiences but could not be explained by the specific podcast tour designs tested. From a practical perspective, the findings provide important insights regarding the usefulness of podcast tours as interpretative media, and also suggest that specific designs are more capable of fostering feelings of social presence.