The dwarf planet Makemake is the planet with a year 310 earth years long.
The dwarf planet Pluto is the planet with a year 248 earth years long.
The dwarf planet Haumea is the planet with a year 280 earth years long.
Mars.
It is 84 Earth years
The dwarf planet Eris best fits this description, with a year about 561 years long.
It is one mercury year long
neptune
Uranus.
uranus
11.68 years
The dwarf planet, Pluto, has a year of 247.9 Earth years.
One year on the planet Neptune is the equivalent of 164.79 years on Earth. A day on Neptune is equal to 16 hours and 6 minutes.