mknewman writes with an article at NASA SpaceFlight which lays out the details of a plan from SpaceX to send a craft to Mars
, using an in-development engine ("Raptor") along with the company's Super Heavy Lift Launch Vehicle. "Additionally, Mr. Musk also introduced the mysterious MCT project, which he later revealed to be an acronym for Mars Colonial Transport. This system would be capable of transporting 100 colonists at a time to Mars, and would be fully reusable. Article is technically dense but he does seem to follow through on his promises!"
This is an endeavor that's been on Elon Musk's mind for a while