"Just a casual Sunday night stroll in St Lucia looking for snacks at OK Express. The hippo returned back to the lake after grazing around town. St Lucia town is surrounded by a large lake and extensive natural habitat for wildlife," read the post.
St Lucia is part of the iSimangaliso Wetland Park, which is home to between 800 and 1,000 hippos.
Park manager Raymond Zulu told TimesLIVE hippos are regularly spotted in the town.
"Once a month we have a visit at the garage. We are all quite used to seeing them. They are not dangerous but nobody goes near them or feeds them. They are good for our town's tourism," said Zulu.