Virtual environments (VEs) very often contain buildings that have to be navigated by users. In the literature, several navigation aids based on maps have been proposed for VEs, but in virtual buildings they have been typically used for single-floor scenarios. In this paper, we propose and experimentally evaluate two different navigation aids for multi-floor virtual buildings, one based on 3D maps and the other based on 2D maps. We compared subjects’ performance with two different types of tasks: search and direction estimation. While the 2D navigation aid outperformed the 3D one for the search task, there were no significant differences between the two aids for the direction estimation task. Categories and Subject Descriptors H.5.1 [Information interfaces and presentation]: Multimedia Information Systems – Artificial, augmented, and virtual realities. H.5.2 [Information interfaces and presentation]: User Interfaces – Interaction styles, evaluation. I.3.6 [Computer graphics]: Met...