At this scale, planetary circumnavigation is not something that can be accomplished within a single human lifespan, absent magic like life extension.
This raises some interesting possibilities. There might, for example, be groups dedicated to exploration that do their work over generations. You might now have the first person to circumnavigate the sphere, but a first family or lineage to do so. You could even have a terrestrial version of a generation ship. Maybe a group of pilgrims heads into the wilderness to find a new homeland, traveling for generations before settling down.