The planet with the biggest orbit in our solar system is Neptune.

While Pluto used to be considered the planet with the largest orbit, it was reclassified as a dwarf planet in 2006.

Here's why Neptune has the largest orbit:

* Orbital Period: Neptune takes about 165 Earth years to complete one orbit around the Sun.

* Distance from the Sun: Neptune's average distance from the Sun is about 2.8 billion miles (4.5 billion kilometers).

Keep in mind, "largest" can be interpreted in different ways. While Neptune has the largest orbit in terms of distance and time to complete one orbit, other planets have larger orbits in terms of their elliptical shape.