A navigation system or combination of navigation systems can be used to provide one or more navigation modalities to track a position and navigate a single instrument in a volume. For example, both an Electromagnetic (EM) and Electropotential (EP) navigation system can be used to navigate an instrument within the volume. The two navigation systems may be used separately to selectively individually navigate the single instrument in the volume. Disclosed are also systems and processes to determine a shape of the single instrument either alone or in combination with the position of the instrument. The instrument may be navigated with the addition of tracking devices or with native or inherent portions of the instrument.