First chose a state and difficulty by entering the state abbreviation followed by a 1 or 2 – i.e. ‘CA2’. Level 1 is easier with 1-degrees squares, level 2 is 0.5-degree squares. Then, enter the largest city in each grid square of the size based on your difficulty. Only green squares contain answers – others may not have a corresponding place (i.e. no places, all unincorporated).