The Estonian language has six locative cases, descended from the locative cases of Proto-Finnic. They can be classified according to a three-way contrast of entering, residing and exiting a state, with two sets of cases: inner and outer. Though they are not traditionally considered so, the essive and translative cases also can be considered locative, for a system of eight (out of fourteen) cases.
The only Estonian semantic cases not included in this system are the terminative (which even might be called locative), and the pair of abessive and comitative.
For some nouns, there are two forms of the illative: the regular suffix -sse (e.g. keelesse), added to the genitive stem, and an alternative, short form, which is either consists of a different suffix (keel > keelde) lengthening (e.g. maja > majja, [ko:l] > [ko::li]), and/or other change in the word. The always regular -sse illative ending is a newer innovation, and can sometimes have a slightly different meaning than the old "short form" illative, the later having the concrete locative meaning (e.g.: tuppa 'into the room'), and the former being used in other structures that require the illative (mis puutub toasse 'concerning the room...').