In a large bowl season cucumbers with salt and let sweat for 1 hour.
Drain liquids and toss cucumbers with onion slices.
In a small saucepan over high heat, pour in white vinegar and water and stir in sugar until dissolved and liquid turns clear, 3 to 5 minutes.
Pour over cucumbers and onions.
Stir in the dill.
Cover and refrigerate for 1 hour.
Serve cold or at room temperature.