High resolution gamma-ray spectroscopy is one of the most powerful tools to study the structure of atomic nuclei. Since nuclei in the rare-earth region can accommodate the highest values of angular momentum before fission, it has traditionally been one of the most favored domains for the study of “high-spin” states in nuclei. In this presentation a few select examples will be featured to illustrate a number of beautiful, dramatic and often unexpected, structural changes that take place in these nuclei as they evolve with increasing excitation energy and angular momentum. The excitement generated by the many fascinating discoveries in this region of nuclei has played a major role in pushing the advancement of increasingly sensitive gamma-ray detector systems, or “gamma-ray microscopes”, through the decades. The resulting 4π gamma-ray arrays, or “Gamma-Spheres”, continue to reveal fascinating new scientific phenomena at the limits of isospin, excitation energy, angular momentum, temperature, and charge. Another huge leap forward in the resolving power of germanium based detection systems is now taking place via the development of gamma-ray tracking arrays which when combined with new accelerator developments, promises a most exciting future to the field of high-resolution nuclear spectroscopy.