There are various towns within striking distance of Mossel Bay and the Robinson Pass offering cellar tours, wine tasting and other interesting activities.
At the foot of the Outeniqua Pass between George and Oudtshoorn at the turn off to the Montagu Pass is Herold Wines. They offer a cellar tour, wine tasting, bring your own picnic, there's a mountain pool and also farm and fynbos walks.
Over the Perdepoort Pass is Domein-Doordekraal, and at De Rust is Excelsior - Vlakteplaas, where you can enjoy some delicious muscadel.
In Oudtshoorn visit the Kango Wine House which has a dierse range of wines.
On the N12 to George there is Grundheim Wines.