A Curious Collage

Near our basecamp we were greeted by a set of peculiar city ruins. The architecture showed characteristics of every civilization we've encountered so far - including our own! However, the material composition is similar to what we use to establish base camps during planetary colonization. This is strange because these materials could never hold out for multiple decades, let alone the age our scanners determined these ruins to be. It's unlikely for these ruins to have belonged to a mysterious precursor, yet the scanners persist in their conclusion. What could be at play here?

The command below will trigger the "A Curious Collage" event in Stellaris:

When this event fires, you can choose between the following option:

• Intriguing.
  • Society: +None to None