Luke says that Jesus goes ahead 'ascending up to Jerusalem.' In biblical language people routinely go up to Jerusalem and down from it, even when their compass direction might suggest something else.
The expression reflects the city's physical elevation and its importance as the destination of pilgrimage.
Jerusalem stands in the Judean hill country at an elevation well above the Jordan Valley and Jericho. A traveler approaching from Jericho therefore makes a substantial climb. Other approaches also culminate in ascent into the hill country.
Because Jerusalem contained the Temple, 'going up' could also carry the associations of pilgrimage and worship. Geography and sacred significance reinforce one another rather than requiring a choice between literal and symbolic meanings.
The phrase helps modern readers visualize Jesus' final approach to the city as an ascent rather than a level walk. It also connects his journey with generations of pilgrims who went up to Jerusalem for Israel's festivals.
Luke's travel language therefore keeps both the landscape and the approaching climax of Jesus' mission in view.