I visited Le Verdon in October, the port itself is an abandoned container terminal in the middle of nowhere.
We walked about 2.5 miles up the coastal path past the big marina to Pointe de Grave, the ferry terminal for Royan. It is a pleasant 20 minute crossing to Royan and the town is a post 1950s resort (empty in October and closed on Mondays). We did not have a lot of time as the ferries were on an Autumn schedule but I understand in summer they run more regularly. If you have more time there is a museum and a casino in the town together with beautiful beaches the Notre-Dame dr Royan church is worth a stop, the sea front restaurants provide a decent lunch with the locals and french tourists. On your way back you can visit the Phare de Grave lighthouse if it is open (it was on Mondays).