Cessna 210 Centurion / Turbo Centurion 210C; 210D
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Private
Flight Crew Last 90 Days 150; Flight Crew Total 2400; Flight Crew Type 1000
Other / Unknown; Situational Awareness
Deviation / Discrepancy - Procedural Published Material / Policy; Ground Incursion Runway
Flight Crew Became Reoriented
Human Factors; Procedure
I inadvertently landed on a closed runway.  I was unaware of the runway closure; which I subsequently discovered had just gone into effect that morning.  I did not see the runway closed markings and after landing saw cones blocking the entrance to the ramp from the taxiways; so I took off and after circling; saw the yellow x markings which were placed off the ends of the runway in grass; not on or near the runway numbers which were clearly visible.  In addition to less than optimal runway closure markings; I had not noticed any posted notice of the planned closure despite flying into the airport and walking through the terminal building multiple times in the last few weeks.
C210 pilot reports landing at a closed airport which was not detected until after landing. The reporter elects to depart and while circling after takeoff; yellow X's are noted off the end of each runway on the grass.