Slice the oranges into 1/4-inch rounds and remove any seeds.

In a saucepan, combine water and sugar; bring to a boil. Add orange slices and simmer for 15 minutes until tender.

Remove the slices from the syrup and place them on a cooling rack to dry for at least an hour.

Melt the dark chocolate in a bowl using a microwave or double boiler until smooth.

Dip each orange slice into the melted chocolate, allowing excess to drip off before placing them back on the cooling rack.

Sprinkle sea salt on top while the chocolate is wet, then refrigerate until set (about 30 minutes).