You can create semi-permanent areas of magical effect by tying spells to a particular location.

You are able to tie spells of an abjurative and divinatory nature to locations by imbuing some of your arcane power into a stationary focus. The caster must have prepared the spell and must provide any material components or focuses the spell requires.

Only stationary objects such as walls, pillars, flagstones, etc. may be warded in this way. Any size object may be warded, but the object’s size counts against the radius of the effect. Thus, a 10’x10’ well could be warded, but one 5’x5’ area would have to chosen as the focal point of the ward. Attempting to ward an object larger than the ward’s area causes the cleansing ritual to fail automatically. Creatures and loose objects may not be warded, though an object could be embedded or buried in the place to be warded. Should a warded object ever be moved, the enchantment is immediately lost. A ward can be woven for a base price of total spell levels x caster level x 100 gp (a 0-level spell counts as 1⁄2 level). The market value of weaving a ward is equal to its base price.