In this article we review a set of methods for exploring the space of a set of collective variables, and to reconstruct the associated Landau free energy in presence of metastabilities: Temperature Accelerated Molecular Dynamics (TAMD), its extension, Temperature Accelerate Monte Carlo (TAMC), and the Single Sweep Method (SSM). TAMD and TAMC can be used for both exploring and reconstructing the Landau free energy landscape. However, SSM is more efficient at accomplishing this last task. We illustrate the use of these methods by presenting their application to the nucleation of a Lennard-Jones crystal from its melt, and the H-vacancy migration in an NaAlH6 crystal.