Through the use of the masonry spell (HELP SPELL MASONRY), player owned
castles
(HELP CASTLES) can be upgraded to settlement status. Castles with this
status 
change from a private-by-default to a public-by-default status, meaning
that 
rather than only allowing access to the owner and people on the friends
list, 
settlements allow all users to enter, save for those specifically barred
via 
the enemy list.

Note that while the enemy setting is only useful at present in settlements,
the
friend setting is relevant for more than just castles, as being set as a
friend
in a particular room can affect things such as who is damaged by traps or
other
defenses.

Settlements are useful for situations where you want all players to be able
to
visit an establishment, whether to do business, to socialize or to regen or

just for the joy of establishing your own player-run city.

Please note also that normal castle rules apply to settlements, despite
their 
public nature. Please use your best judgment in what you make publicly 
accessible. Among other things, this means that, in the event of a dispute,
all
objects left in a settlement, as with any other castle, are considered the 
property of the owner, who may control others access to those objects as
they
see fit. Anyone granted access to the objects is presumed to have
permission to
use them as they also see fit. Nonetheless, players are encouraged to
respect 
other members of the community, as well as those individuals terms upon
with 
they make their spaces available, and players may still be subject to
penalties
for griefing or harassment when applicable.

Cost and sharing:

Remember that establishing a settlement is expensive (roughly the cost of
adding
ten rooms). This is not meant as a gold sink, but as an incentive for
player
cooperation. If you're considering creating a two-room settlement, we
strongly
advise you to reconsider. Instead, find other players who are also
interested in
making settlements and cooperate, adding your two rooms onto their larger
edifice. Settlements are public spaces, after all. There's no need for
everyone
to have their own.