The Urban Ironwood City offers a culmination of protecting the rain forest of Borneo, based on Sustainability Development Goals from the UN as backbone system. Consist of 5 cluster with 5 sub-cluster, and 5 District, The Core City cluster placed in between Balikpapan and Samarinda, providing macro connection as well as protection to the conserved forest. The 4 naturally placed clusters, between reservoir and rivers, are eco-cluster with 5 fingering districts, surrounded by buffer zone as development control. These clusters give room for expansions within the buffer zone. Material use is Kayu Ulin, the endemic tree of Borneo, converted to Cross-Laminated Timber, to create a sustainable material. We hope that the idea could give Indonesia contribution towards being Indonesia as Developed Country in year 2045, when the country celebrates her 100 years of Independence.