A guldin was, in Orion culture, a facility in which the Grey Orions were kept imprisoned and kept alive. A guldin consisted of a set of quarters equipped with all the medical and cybernetic technology and supplies necessary to keep a Grey Orion in reasonable health and operation. They were often sealed against the outside world, with an array of life-support technology, such as air-, water-, and food-recycling mechanisms. This was because exposure to impure water, food, or even air, to light or certain environmental conditions, and even minor accidents, could kill many of the sickly and sensitive Grey Orions. Thus they could rarely leave.