We present the design of an interface that provides continuous navigational support for indoor scenarios where localization is only available at sparse, discrete locations (info points). Our interface combines turn-by-turn instructions with a World-inMiniature (WIM). In a previous study, we showed that using an Augmented Reality WIM at info points, and turn-by-turn instructions elsewhere, is a valid support for navigation inside an unknown building. In particular, we highlighted that users value the WIM as a tool for monitoring their location in the building. In this work, we focus on using the WIM continuously, not only at info points, to support navigation. We adapt the WIM views to the quality of localization by transitioning within Mixed Reality: we use Augmented Reality to provide an overview of the whole path at info points and Virtual Reality to communicate the next instruction when localization is not available. Our results from a new user study validate our interface design and show that users exploit not only turn-by-turn instructions but also the WIM throughout the path, to navigate with our interface. This paper provides insight on how a low-infrastructure indoor solution can support human navigational abilities effectively.