Squeeze the juice from the orange and set the juice aside. In a small saucepan over high heat, combine the orange rind and the water and bring to a boil. Cook for 5 minutes, set aside.
Sort the cranberries, discarding any soft ones. Add orange juice, orange rind, sugar, salt. Bring to a boil over high heat, then reduce the heat to low and cover the pan partially. Simmer gently, stirring occasionally, until the sauce thickens, the cranberries have burst, 10 to 15 minutes.
Transfer the cranberry sauce to a heatproof bowl and let cool for 1 hour before serving. Or cover and refrigerate; bring to room temperature before serving.