Inflammatory diseases of the aorta fall under the umbrella term "aortitis" and encompass a broad spectrum of autoimmune and infectious disorders. Giant cell arteritis and Takayasu arteritis represent the most common causative primary large vessel vasculitides. Isolated aortitis is a further important entity, whilst IgG4-associated systemic disease today represents yet another disease entity belonging to this group. Clinical presentation is highly variable, ranging from asymptomatic incidental findings to acute aortic syndrome due to rupture. Diagnostic imaging techniques form the cornerstone of the diagnostic workup. These techniques should also be used in screening for diseases with frequent aortic involvement. The treatment approach depends on the underlying disease and on the extent of aortic damage secondary to vascular inflammation. Against this background, differentiation between autoimmune and infectious aortitis is therefore necessary due to the contrasting treatment strategies. The present article is intended to provide the internist with an overview of this heterogeneous disease entity.