Star Wars artist Chris Voy who has worked on both Star War: The Clone Wars and Star Wars Rebels has a rather interesting piece of artwork on his website portfolio.
Along with a pair of shots of Capital City on Lothal, Voy has a piece entitled, “Rebels Takobo City Designs” which features three renditions of a circular city on what appears to be a reflective and possibly frozen surface.
Takobo City is a name that doesn’t as far as I can tell exist in Star Wars canon. It is not clear if this was an abandoned design not used for Star Wars Rebels season one or if this might be our first look at a new location in season two.
Thanks to Spectre Sam for the tip.