Much of the information designed to help people navigate the built environment is conveyed through visual channels, which means it is not accessible to people with visual impairments. Due to this limitation, travelers with visual impairments often have difficulty navigating and discovering locations in unfamiliar environments, which reduces their sense of independence with respect to traveling by foot. In this paper, we examine how mobile location-based computing systems can be used to increase the feeling of independence in travelers with visual impairments. A set of formative interviews with people with visual impairments showed that increasing one's general spatial awareness is the key to greater independence. This insight guided the design of Talking Points 3 (TP3), a mobile location-aware system for people with visual impairments that seeks to increase the legibility of the environment for its users in order to facilitate navigating to desired locations, exploration, serendipitous discovery, and improvisation. We conducted studies with eight legally blind participants in three campus buildings in order to explore how and to what extent TP3 helps promote spatial awareness for its users. The results shed light on how TP3 helped users find destinations in unfamiliar environments, but also allowed them to discover new points of interest, improvise solutions to problems encountered, develop personalized strategies for navigating, and, in general, enjoy a greater sense of independence.