When designing ancient temples consider their general region and how they are situated within the local terrain. They may be built into a cliffside, be partially buried by desert, be hidden deep within a jungle, be entrapped within an arctic region, or reside on a holy island. There may be waterfalls surrounding the ruins, giant trees or vines that have grown through them, or they may be slowly sinking into the surrounding marsh.

The architecture of the temple is another important aspect and may reflect an old religion or an ancient civilization. The entrance into the temple, or into deeper chambers within it, may require a key or may involve a hidden doorway. The ancient temples of fantastic worlds often hold secret chambers within them.

Ancient temples in fictional worlds may contain traps or terrain hazards. Consider pitfall traps, blade traps, and boulder traps as options. There may be ancient automated systems that are triggered when adventurers enter or when a ritual is completed.

Inside may contain reflecting pools, altars, obelisks, statues, crypts, and ancient tombs.

Altars

Obelisks

Statues

Ancient temples may feature waterfalls, sandfalls, or lavafalls. As is often the case with waterfall elements, there may be secret chambers hidden behind their cascades.

Ancient temples are often dungeons in game worlds.

In postapocalyptic worlds, locations like movie theatres, malls, and capital buildings may be mistaken for ancient temples.

Ancient temples are an opportunity to explore a fictional history. They may have been built by an ancient civilization to honor a fictional god or be a place of prayer for a fictional religion.