To be fair, that would probably be navigation by naturally observable indicators such as the rising or setting sun, shadows over the day, locally / seasonally reliable stars for your area, and knowledge of local fauna/wave patterns.

After getting interested in sailing again (after 20 years) last year through multihull vessels, I started reading about the evolution of multihulls in the Pacific and then began looking at traditional navigation techniques. Following that, I was wondering for fun whether it would be possible to plot one's position given a rough time, rough position guestimate, and perfectly measured horizonal inclination, lens property and visible to 'the naked eye' star positions (ie. visible to the naked CCD at evening time = high ISO, noise and short shutter speed to failitate clarity in rough seas). My conclusion was yes, it's possible, with sub-GPS accuracy but accuracy which would be good enough to get you reliably between certain locations in certain seasons even on a sailboat.

I was surprised to read that some ICBMs allegedly used astronomy and pre-loaded landform navigation to avoid issues with jamming, and that fat databases of precise naked-eye type visible star locations are widely available, indeed so is software for reducing them to identities from an image input.