The invention relates to a tower part (6) for a wind turbine (1) comprising at least one wall segment (9) and at least one aperture segment (10) including at least one aperture (7). The wall segment (9) and the aperture segment (10) being connected by connecting means and the aperture segment (10) is of a substantially uniform thickness and is thicker than the thickness of the wall segment (9). The invention further relates to an aperture cover system for covering at least one aperture (7) in a tower part (6) for a wind turbine (1). The system comprising cover plates and attachment means for attaching the system to the tower part (6), wherein the attachment means do not affect the fatigue limit of the tower part (6). Finally the invention relates to a method for manufacturing a wind turbine tower part (6) and uses hereof.