The state Department of Natural Resources announced permanent protection this week for an area it's calling a great natural treasure. Pine Bend Bluffs is located between Highway 52 and the Mississippi River in Inver Grove Heights and includes more than 150 acres of oak savanna and prairie. The protected land has been designated a "Scientific and Natural Area," which offers the highest level of state protection but allows for passive activities like hiking and bird watching. Al Singer, the DNR Metro Greenways Program Manager, led the effort to buy the land. He says it took almost three years to put the deal together.