The word "gunungan" in Javanese language means "like a mountain", or "similar in shape to a mountain". Gunungan is one of the physical manifestation of thankfulness offerings ("sajen wilujengan" in Javanese) which is particularly made for specific purpose in a traditional ceremony such as "Wilujengan Negari" on every garebeg.

There are six kinds of gunungan which are usually made in the Garebeg ceremony, as follows: Gunungan Lanang, Gunungan Wadon, gunungan Gepak, Gunungan Pawuhan, Gunungan Dharat, and Gunungan Kutug bromo. from the sixth gunungan, there are only five gunungan displayed on the yearly Garebeg ceremony, such as Gunungan Lanang, Gunungan Wadon, Gunungan Gepak, Gunungan Pawuhan and Gunungan Dharat. Gunungan Kutug Bromo is only made one every eight years on the year of Dal (year in Javanese calendar), to be served in the Garebeg Mulud Dal.

The offerings of gunungan is a sacred offerings which has been prayed with "mantra". Therefore gunungan is considered magic and able to refuse bad situation "tolak bala". This common sense is strengthened by a condition that the offerings is based on "kain bangun tulak", something like clothes with magical power. The special building for gunungan is called as omah gunungan (omah = house).