How does social presence influence the perception of a physical environment? People think about social relationships in terms of space. For instance, when drawing routes on maps they draw paths closer to friends than strangers (Matthews & Matlock, 2011). How does the mere presence of a friend alter spatial reasoning? Here, participants imagined working for an outdoor magazine. They viewed photos of bridges one might encounter while hiking. Some participants were told they preferred crossing bridges last (in a group), while others were told they preferred crossing them first. All participants estimated bridge length. Those who crossed last, and imagined their friends on the other side of the bridge, provided reliably shorter length estimates than those who crossed first and imagined their friends standing immediately behind them. These results provide new insights into how social presence can influence our perceptions of physical environments.