A mikveh must contain a little more than 500 liters of water and have seven steps leading down into the water basin. To be considered kosher, that is, to be suitable for the daily ritual washing, the water must be taken directly from nature. This includes spring-, ground- and rainwater, explaining why many older mikvehs were constructed at the local groundwater level. In modern times, rainwater is also commonly used. The body must be in complete contact with this so-called living water. To achieve this, one submerges the head naked, without any jewelry or makeup. This process is called: Tvilah