A Google search provides the following.
How can I find a location using GPS coordinates in iPhone Maps?
To look up a specific location using your iPhone, only the latitude and longitude coordinates are needed. If you don't have an address for a place, you can enter the GPS coordinates directly into the Maps location and the location will be displayed.
1. Open the Maps app.
2. Tap Search at the bottom of the screen.
3. Enter the latitude and longitude coordinates in the search bar.
4. Coordinates can be in decimal degree format or degrees, minutes, seconds.
Here are examples of properly formatted coordinates:
44 35′25″n 104 42′55″w
or
44.5903 -104.7153