The best surface for positioning a shipping container is a level, solid, and stable surface, such as a concrete slab or compacted gravel. The surface should be able to support the weight of the container and its contents, as well as withstand any shifting or movement of the container during loading and unloading. It is also important that the surface is level to ensure that the container is stable and not at risk of tipping over.   Additionally, the surface should be well-draining to avoid water pooling around the container which can cause rust and corrosion over time. If the container will be used for long term storage, it's important to consider the potential for flooding or groundwater table, a level surface with good drainage will help to mitigate these risks.   It's also important to consider the access to the container, a surface with good access for loading and unloading, as well as for any heavy equipment that may be needed, such as cranes or forklifts, will make the process of moving the container and its contents much easier.