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Our ability to return to the start of a route recently performed in darkness is thought to reflect path integration of motion-related in- formation. Here we provide evidence that motion-related interocep- tive representations (proprioceptive, vestibular, and motor efference copy) combine with visual representations to form a single multi- modal representation guiding navigation. We used immersive virtual reality to decouple visual inputfrom motion-related interoception by manipulating the rotation ortranslation gain of the visual projection. First, participants walked an outbound path with both visual and interoceptive input, and returned to the start in darkness, demon- strating the influences of both visual and interoceptive information in a virtual reality environment. Next, participants adapted to visual rotation gains in the virtual environment, and then performed the path integration task entirely in darkness. Our findings were accu- rately predicted bya quantitative model in which visual and intero- ceptive inputs combine into a single multimodal representation guiding navigation, and are incompatible with a model of separate visual and interoceptive influences on action (in which path integra- tion in darkness must rely solely on interoceptive representations). Overall, our findings suggest that a combined multimodal represen- tation guides large-scale navigation, consistent with a role for visual imagery or a cognitive map. [ABSTRACT FROM AUTHOR]