In this paper we present how context can be used to support an user that is navigating both virtually and physically an information system. Navigation is seen as the act of going from one object to another. Navigation can be virtual like the Web navigation or physical like with a digital museum guide. We start by giving a formal definition of context that relies on the notion of proximity. An important peculiarity of this definition is that it permits us to build context according to several dimensions at a time, like the thematic dimension, the physical dimension or the temporal dimension. This definition permits us to build two applications that ease the navigation by constantly proposing relevant destinations to the navigating user. The first application is an assistant to help an user that navigates the web. The second application is a digital guide that permits the user to navigate through an information system composed of digital photos.