Kalniņš J., Krastiņš J. Shape of apertures in Riga wooden buildings. In wooden buildings, shapes of apertures determine its fill and establishment of decorative welt. Characteristic forms of apertures of wooden building are close to square, with form of round arch, flatly bent lintel, with tapered upper parts, with pointed, triangular and rectangular shape, that can be observed in all architectural styles. Baroque dormer apertures most often are with flat bent upper part, ellipse or close to round formed different solution interpretations. Different geometrical shapes of apertures can be observed in gables and pediments – circular, simple segment, rhombic, ellipsis, triangular, star shaped, and of shapes characteristic basic windows. Apertures in pediments and gables form different decorative and compositional features. All different shapes of apertures as well as semi–detached windows are peculiar for apertures in antiques and dormers. In forms of apertures can be behold the most characteristic hallmarks of each architectural style. The choice of wooden building apertures within architectural styles forms the arrangement of apertures and their architectural trim, which is unique part of cultural and historical heritage in Riga cityscape.