Charuta

Charuta was the initial colony in the Aradin system. It was the point from which all of the other colonies originated and the one who funded them. There was little concern for conservation, and the cities blossomed quickly. A few parks were set aside, but at this point there is very little natural space between buildings.
The planet is practically one giant city now, and can be extremely overwhelming for people unaccustomed to it. Some natives have never seen a tree that wasn't deliberately placed by a city planning committee of some kind. Migraines are common, especially among those who haven't lived there long, and it is increasingly difficult to get away from the constant lights and city noise.
Being the first colony, Charuta is home to a lot of the system's government. There have been recent efforts to move the main bases for interplanetary matters into orbit in an attempt to make them a little more impartial, but so far only the Bureau has managed it. The planet is also the one with the most wealth, by a very large margin. A lot of it is just thanks to time -- people have lived on Charuta longer than any of the other planets -- and part of it is the government work and accumulated riches from colonizing efforts.
It's a stressful place to live, but still largely considered one of the best options in the system.
Not that anyone can easily afford to move there.

Geography

Charuta is a smaller planet, but they've managed to fit far more people on it than anyone expected. The continents are very spaced apart -- not that it's much of an issue with atmosphere-rated ships readily available -- and all but covered in cities of varying densities.
The climate is pleasant enough, with few places seeing temperatures extreme enough to be a real threat. The larger cities can create their own small pockets of weather, but that's usually just unexpected wind or precipitation.
The landmasses don't vary much in height; there are a few areas that have been preserved as parks, and most of them are either some kind of forest or a section of nicer coastline. Conservation was not a priority, but the government is determined to keep at least a few chunks of the planet as they found it.

Type

Planet