A method of operating an industrial vehicle in a navigation system comprising the industrial vehicle, one or more sensors coupled to the industrial vehicle, a mobile computer operably coupled to the industrial vehicle, and an environment based navigation module comprised in the mobile computer, wherein the method comprises: starting-up the industrial vehicle, wherein the industrial vehicle pose is unknown; using the mobile computer to process measurement data from the sensors, wherein the measurement data is indicative of the presence of pre-positioned objects or unique markers within a range of the sensors within the physical environment , and using the mobile computer to determine initial industrial vehicle pose prediction data from the measurement data, characterized in that : the pre-positioned object or unique marker correspond with a sub-area of the physical environment, and each sub-area of the physical environment corresponds to a unique marker; the initial pose prediction data is sufficient to determine the sub-area in which the industrial vehicle is positioned, but is insufficient to determine a location of the industrial vehicle within the determined sub-area; and the method further comprises: using the mobile computer to select a sub-area based on the initial pose prediction data and obtain a sub-area map from an overview map of the physical environment; using the environment based navigation module to refine the initial pose prediction data for the industrial vehicle using the sub-area map and features observable by the sensors from the selected sub-area to generate a new vehicle pose; and operating the industrial vehicle based on the new vehicle pose. starting-up the industrial vehicle, wherein the industrial vehicle pose is unknown; using the mobile computer to process measurement data from the sensors, wherein the measurement data is indicative of the presence of pre-positioned objects or unique markers within a range of the sensors within the physical environment , and using the mobile computer to determine initial industrial vehicle pose prediction data from the measurement data, characterized in that : the pre-positioned object or unique marker correspond with a sub-area of the physical environment, and each sub-area of the physical environment corresponds to a unique marker; the initial pose prediction data is sufficient to determine the sub-area in which the industrial vehicle is positioned, but is insufficient to determine a location of the industrial vehicle within the determined sub-area; and the pre-positioned object or unique marker correspond with a sub-area of the physical environment, and each sub-area of the physical environment corresponds to a unique marker; the initial pose prediction data is sufficient to determine the sub-area in which the industrial vehicle is positioned, but is insufficient to determine a location of the industrial vehicle within the determined sub-area; and the method further comprises: using the mobile computer to select a sub-area based on the initial pose prediction data and obtain a sub-area map from an overview map of the physical environment; using the environment based navigation module to refine the initial pose prediction data for the industrial vehicle using the sub-area map and features observable by the sensors from the selected sub-area to generate a new vehicle pose; and operating the industrial vehicle based on the new vehicle pose. using the mobile computer to select a sub-area based on the initial pose prediction data and obtain a sub-area map from an overview map of the physical environment; using the environment based navigation module to refine the initial pose prediction data for the industrial vehicle using the sub-area map and features observable by the sensors from the selected sub-area to generate a new vehicle pose; and operating the industrial vehicle based on the new vehicle pose. <EOS>