16-11-600 forbids entry onto property after receiving notice prohibiting entry.  It also requires that if you enter lawfully and are later told to leave, it would be trespassing if you stayed.  Even if there were no "No Trespassing" signs, other things may constitute notice.  For example, if you had to climb over a fence to get onto the property, the fence would tell you that the owner of the property does not want you on the property.  The penalty in South Carolina for trespassing is a fine up to $100 or up to 30 days in jail.