[2] Merrick County is part of the Grand Island, NE Metropolitan Statistical Area.

[6] When first formed, the county was bounded on the south by the Platte River, and by straight lines on the north, east, and west; enclosing 180 square miles (470 km2) of the Pawnee Reservation, which had been established in 1857.

In 1873, the state legislature removed these reservation lands from the county, leaving it with a jagged northern border from which narrow panhandles extended northward from the northeast and northwest corners.

[7] The terrain of Merrick County is low rolling plains, sloping to the east and northeast.

The Platte River flows northeastward along the southeast border line of the county.

[9] As of the 2000 United States Census,[15] there were 8,204 people, 3,209 households, and 2,307 families in the county.