Complex sentence: It leaves from Puy-en-Velay and crosses the countryside in stages to the basque village of Ostabat near which it meets up with two of the other routes, the via Turonensis and the via Lemovicensis which merge a little earlier.
Split into simpler sentences: It leaves from Puy-en-Velay and crosses the countryside in stages to the basque village of Ostabat. Near there it merges with two of the other routes, the via Turonensis and the via Lemovicensis which merge a little earlier.