Augmented reality (AR) technology is commonly used in education. AR offers a combination of the virtual and real world; thus, it can help students in learning abstract and complex subjects. The purpose of the current study was to determine the impact of mobile AR technology on achievement, cognitive load levels and views of 95 first-year university students (40 in the experimental group and 55 in the control group) enrolled in a geography course in the social sciences education department of the education faculty of a university in Turkey. A sequential explanatory design, a mixed method type of research, was used. The data were collected using an achievement test, a cognitive load scale, and a semi-structured interview form. The results of the study showed that AR increases students' achievement and decreases their cognitive load levels, and the students' views about AR technology were positive. Consequently, it can be stated that mobile AR technology is a useful tool for teaching geography, especially geomorphology topics.