You might know that there are about 40 portals on Earth. Some are underwater, some high up the mountains. I think yours is a portal cloaking as a door. Portals lead to other realities by way of lazing together the space fabric of different dimensions. Portals are Quantum, and once you enter you become Quantum as well. So it could lead you anywhere. But I KNOW that Earth portals always lead to long forgotten and legendary places. Maybe not El Dorado, but the portal might lead you to hidden treasures on another planet. But in all cases entering will expand your consciousness.[100 words]
;)