Wash the cucumbers under running water and slice them into thin rounds. Peel and slice the onions.

In a large mixing bowl, combine the cucumber slices and onion slices. Sprinkle salt over the top and let sit for about 2 hours to draw out moisture.

After 2 hours, drain the cucumbers and onions in a colander and rinse them under cold water to remove excess salt. Allow them to drain well.

In a medium-sized pot, combine white vinegar, sugar, mustard seeds, celery seeds, turmeric, ground ginger, and ground cinnamon. Bring the mixture to a boil over medium heat, stirring until the sugar has dissolved.

Once boiling, add the drained cucumbers and onions to the pot. Stir to combine and bring back to a gentle simmer for about 10 minutes.

Remove the pot from the heat. Using a ladle and a funnel, pack the hot pickles into sterilized canning jars, leaving a little space at the top.

Seal the jars with lids while the contents are still hot. Allow the jars to cool to room temperature before refrigerating.

For the best flavor, let the pickles sit in the refrigerator for at least 24 hours before serving. They can be stored in the refrigerator for up to two months.