Go through your maps and find the birth city of each member of your family. Place a podgeable shape over the city and position it where you want it then trace around it onto the map.
Cut out the map shapes, cutting the shape a little smaller than your tracing line.
Paint a moderate layer of Mod Podge onto the back of each podgeable shape and to the FRONT of each map piece.
Press the back of the podgeable shape onto the front of the map piece. You will have a short window of time where you can move the piece around to position it. Don't wait too long or it will start to dry! Get it in place then press to make sure it's flat. Next paint a layer of Mod Podge onto the back of the map to seal it. Allow the shapes to dry.
Measure a piece of cord to about 18-inches long. Run the cord through the hole at the top of the shape and tie the cord in a knot. Add another shape and tie again. Continue until all maps are added. Tie two more knots at the end.
Run one end of the cord through the keyring. Tie the cord loosely once, then tie in a second knot, and leaving a loop so that the keyring can move freely, tighten those two knots together. Secure the knot with some white craft glue and leave it to dry. Snip off the excess cord with scissors.