What is a ha-ha, and what is it used for?
Flufferin is right. I may add the other apology it was used in dignified houses was that it cannot be seen from the house, and so did not block the prospect over the surrounding countryside.
If this is a serious garden question, it refers to a trench type boundary barrier used to maintain livestock from gardens without a fence. Kind of a ditch next to a steep wall on the garden side so the animals coundn't cross. It was common within France but brought to England by the famous landscape architect Capability Brown. Well, the permanent status can vary according to who used it. It can either be surrounded by reference to a vagina, which is a key organ of teh feminine reproductive system. It also could refer to a penis, a major organ in the masculine reproductive system. God, how old are you?
Answers: How old is fixmybro? I suggest she look at the category, "Garden & Lanscape". A ha-ha has nil to do with genitals. It is a sunken wall or fence adjoining to a trench, which keeps animals from crossing over. The purpose is an uninterrupted view of the manor estate beside the animals at a safe distance from the manor. The barrier of the ha-ha is invisible. Several can be found within England.