Marco Polo works up to 2 miles (3.2 km) in line-of-sight situations. Expect approximately 1/2 mile to 1 mile (.8 to 1.6 km) in mildly rolling terrain with moderate vegetation. Your individual performance will depend on the specific conditions in the area of use, such as terrain, vegetation, and obstructions. If your pet is beyond Marco Polo’s initial range, you can expand the range by walking or driving around the areal until you come within range. You can also check out this blog post for some customer examples and videos which should provide some additional guidance for determining Marco Polo’s range in your particular conditions.