Location discovery is a task of fundamental importance in wireless ad-hoc networks. The standard localization problem is difficult due to presence of errors in distance measurements and also the need to minimize communication cost. In addition, in real-life situations, there is also a need to consider the existence of obstacles when solving localization problem and interpreting measurements. Obstacles are defined as objects in the instrumented field that significantly alter (prolong) distance measurements. This problem has not yet been properly addressed so far due to its computational intractability and difficulty. Our goal is to introduce conceptual approaches, develop algorithms and software, and also validation techniques to identify and localize obstacles during simultaneous location discovery. The starting point is formulating location discovery as a nonlinear function minimization problem...