The word "gunungan" in Javanese language means "like a mountain", or "similar in shape to a mountain". Gunungan is one of the physical manifest 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.

Gunungan Gepak stands as a unit of small "hills" called "gepak" consisting of fourty baskets of smaller cakes. The cakes are made in five forms in five color, such as red, blue, yellow, green, and black. On the top of the cake there are another baskets full of fruits.

All of the baskets are put on a giant dish structured from wood (more or less 2x1,5 meter) and covered with "kain bangun tulak", also on the four directions, there are yellow clothes.