In a large pitcher, combine the cucumber slices, mint leaves and a splash of the San Pellegrino. Muddle the cucumber and mint until well mashed.
Fill the pitcher halfway with ice. Stir in the Pimm’s and the remaining San Pellegrino. Garnish with half the strawberries and orange slices.
Divide the Pimm’s Cup between glasses filled with ice. Garnish each glass with more strawberries, orange slices, cucumber slices and mint sprigs. Enjoy!