This picture was taken from the watery planet of Juidei.
According
to their history, the planet was not all water initially and has had
dry land. With the melting of the polar ice-caps, the water level
rosed. To overcome this, the inhabitants built floating cities as shown
here.
There
are literally thousands of these floating cities around, many of which
relied on the harvesting of seaweeds as a source of
power-generation.
The inhabitants retained much of their
ancestral clannishness and many of these floating fortress are heavily
defended from possible intruders from other cities.
In the picture above, an interceptor craft greets my craft as I approaches this city.

Escorted by a native interceptor craft, I took a closer view of this particular city as my craft circumvent it.
According to the pilot of the escort craft, the inhabitants on this
city all live within its inner structure and are shielded from the
weather conditions outside.
It is not for me to judge, but I do question the quality of their existence.