Leave Secure route planning in environments with obstacles and threats, which is of first priority for single and multi-Unmanned Aerial Vehicles (UAVs), is the main focus of this study. Planning the optimum route by using genetic algorithms by considering kinematic constraints and terrain conditions is investigated. The terrain used in this study consists of real 3D satellite data of NASA. Thus, access to altitude data is achieved and mountains over the terrain are detected. Real geographic coordinate system is used and the geometric shape of the earth is considered for high precision calculations. While global route planning is made by the GA, local route planning is considered for transitions between waypoints. According to experimental result, usage of multi-UAV brings a great benefit in the fulfillment of the missions in terms of time and performance.