Hematite (α-Fe₂O₃) is a benchmark iron oxide for photo- and electrocatalysis, but the structure of its (0001) facet and the dynamics of its oxidation remain controversial. On this orientation, surface behavior is tightly coupled to the near-surface bulk in both structure and chemistry, which complicates clean interpretation. This thesis investigates the structural and oxidation behavior of α-Fe₂O₃(0001) under ultrahigh vacuum conditions, combining low-energy electron microscopy and diffraction (LEEM/LEED), X-ray photoelectron spectroscopy (XPS), and a collaborative cross-sectional scanning transmission electron microscopy and electron energy loss spectroscopy (STEM/EELS) study. The thesis opens with an overview of iron oxide surface chemistry and hematite phase stability. A methods chapter describes the experimental setup and the preparation of natural single crystals and synthetic films. The next chapter develops a cross-sectional STEM/EELS methodology for the α-Fe₂O₃(0001) surface, refined across four lamella samples, and uses it to provide direct side-view evidence for the magnetite/hematite interface in reduced and oxidized states and to reveal Mn segregation into ferrite-like inclusions in natural single crystals. The final chapter uses real-time LEEM to follow the recovery of the hematite surface from a reduced Fe₃O₄(111)-like layer, showing that complete surface recovery is closely coupled to the lateral growth of the hematite-terminating (H-phase) overlayer. By separating the contributions of temperature, oxygen pressure, and oxygen chemical potential μO, the work establishes the central role of oxygen supply in hematite surface recovery on this orientation, reflecting an interplay between thermodynamic driving forces and kinetic barriers.