Research on the effectiveness of augmented reality (AR) on learning exists, but there is a paucity of empirical work that explores the role that positive emotions play in supporting learning in such settings. To address this gap, this study compared undergraduate students' emotions and learning outcomes during a guided historical tour using mobile AR applications. Data was collected in a laboratory (Study 1; N = 13) and outdoors (Study 2; N = 18) from thirty-one undergraduate students at a large North American university. Our findings demonstrated that learners were able to effectively and enjoyably learn about historical differences between past and present historical locations by contextualizing their visual representations, and that the two mobile AR apps were effective both in and outside of the laboratory. Learners were virtually situated in the historical location in Study 1 and physically visited the location in Study 2. In comparing results between studies, findings revealed that learners were able to identify more differences outdoors and required less scaffolding to identify differences. Learners reported high levels of enjoyment throughout both studies, but more enjoyment and less boredom in the outdoor study. Eye tracking results from Study 1 indicated that learners frequently compared historical information by switching their gaze between mobile devices and a Smart Board, which virtually situated them at the historical location. Results enhance our understanding of AR applications' effectiveness in different contexts (virtual and location-based). Design recommendations for mobile AR apps are discussed.