A Jungle Temple is a rare-structure which can exist in a Jungle biome. Jungle temples can spawn in dense jungle and typically near or in water. There is usually a single entrance which when entered will contain & up/down staircase. The upstairs is an open area which can be used for a bed or crafting table.
The downstairs area contains up to two traps involving trip wire traps & dispenseries which can shoot arrows. Pay attention to sections of the walls covered in leaves as they are likely hiding the dispenser(s). There is a chest at the end of trapped hallway which typically contains rare items or minerals (Gold, Iron, or Diamonds.)
At the bottom of the stairs are three wall switches, using them will open a secret door in the upper level where a player can enter & find an additional chest, or you can just break the blocks thru the wall with a pick-axe.