If a legion marched from rome to the southern border of gaul (in ceasar's time), how long would it take them? Days, Weeks, Months?

Hi, you may be interested in the ORBIS project at Standford University, which calculates travel times during the Roman Empire (tl;dr at least 3 weeks). Linked here:

How long does it take a Roman army from Rome to march to Paris? its about 1100 km. takes about 24 hrs to walk 100 km. so about ? so about 22 days ?