• Traditional or Intelligent
• Demonic
• Portal Hauntings
• Residual

Portals aren't really a new concept, as we've seen them in a lot of sci-fi flicks. But in the real world, portal hauntings are considered controversial as there is little known and the idea is mostly theory or speculation. Portals are thought to be doorways to another world or dimension in which entities travel through. It's speculated that portals are not limited to one location, region or limited to sacred ground. Typically places that experience a wide array of different types of anomalous activity such as glowing balls of light, odd creatures, strange shapes, or unexplained mists or fog, are suspected to have a portal in which these energies are traveling back and forth. Graveyards seem to be a hot spot for these.