Wash the lemons well, scrubbing thoroughly. Using a vegetable peeler, remove the rinds from the lemons, being careful not to include any of the white pith. In a large sterilized jar, combine the lemon rind with the vodka. Seal with a sterilized lid and let stand in a dark place for 6 days.
Day Seven:
In a small saucepan over medium-high heat, combine the sugar and water and bring to a simmer, stirring until the sugar dissolves. Let cool. Transfer the lemon rind from the vodka to the syrup. Reseal the lid on the vodka jar. Transfer the syrup and rind to a sterilized jar and seal with a sterilized lid. Let both jars stand in a dark place for 3 more days.
Day Ten:
Remove the rind from the syrup. Add the syrup to the vodka, adjusting the syrup to the desired sweetness. Strain the mixture through a coffee filter until clear and store in a sealed sterilized bottle.
