That area has considerably expanded since you were last around.
Since the last time you were here, the government had purchased much more land to expand our nation far and wide, but I'm sure you weren't aware of that with your absence. 
mnli hypothesis: Since the last time you were here, the government had purchased much more land to expand our nation far and wide, but I'm sure you weren't aware of that with your absence.  premise: That area has considerably expanded since you were last around.