Giant congenital cavernous haemangiomas are rare. I am presenting this case here because the haemangioma presented as a tumour of the back and led to unexpected obstruction and difficult labour. It remainedantenatally undiagnosed, and caused sudden arrest of an otherwise uncomplicated vaginal delivery because of the tumourmass. This posed as a challenge. In this era of widespread antenatal care, this type of complication is very rare.