Many benefits have been claimed for visualizations, a general assumption being that learning is facilitated. However, several researchers argue that little is known about the cognitive value of graphical representations, be they schematic visualizations, such as diagrams or more realistic, such as virtual reality. The study reported in the paper investigated whether the type of visualization (schematic versus realistic) has an effect on undergraduate students' learning of surveying practices (specifically, "chaining"). The study compared two interactive virtual learning environments, one containing realistic visualizations of terrains and instruments, and one containing schematic graphical representations. Results of an experiment with 62 students show that there were not significant differences in learning between students who were exposed and interacted with the realistic visualizations versus those who interacted with the schematic ones.