<prompt> The most common benign tumour of the orbit isHaemangiomaOptic nerve gliomaBenign-mixed tumourMeningioma  <response>: Vascular tumours : Vascular tumours are the most common primary benign tumours of the orbit. These can be either haemangiomas or lymphangiomas. Haemangiomas are fuher divided into two types -- capillary and cavernous. Ref:- A K KHURANA; pg num:-393 