Share this page Project Green Hollistic System 2.0 Climate Resilient Cities The Green Holistic System (GHS) is an innovative circular and nature-based system targeting sustainable water management Project Green Hollistic System 2.0 Climate Resilient Cities The Green Holistic System (GHS) is an innovative circular and nature-based system targeting sustainable water management Project Green Hollistic System 2.0 Climate Resilient Cities The Green Holistic System (GHS) is an innovative circular and nature-based system targeting sustainable water management