Possible Clues:

• Area about to be bordered by a jail
• Amount of space about to be confined?
• Area of land opening to excursionists in current fashion
• A pen enclosing about this amount of land
• Extent of bill throwing European into fury
• Area where a Native American located precious metal
• Amount of ground flier, in reverse gear, can cover
• Area where one keeps changing gear
• A pound the military accepted for getting measure of land
• One holds on to a good quantity of land