An example UAV landing structure includes a landing platform for a UAV, a cavity within the landing platform, and a track that runs along the landing platform and at least a part of the cavity. The UAV may include a winch system that includes a tether that may be coupled to a payload. Furthermore, the cavity may be aligned over a predetermined target location. The cavity may be sized to allow the winch system to pass a tethered payload through the cavity. The track may guide the UAV to a docked position over the cavity as the UAV moves along the landing platform. When the UAV is in the docked position, a payload may be loaded to or unloaded from the UAV through the cavity.