Lignes Express operates a bus from Castellane to Nice 4 times a day. Tickets cost $18 - $24 and the journey takes 1 h 44 min. Alternatively, Lignes Express operates a train from Castellane to Nice 4 times a day. Tickets cost $10 - $13 and the journey takes 58 min. French Railways (SNCF) also services this route hourly.
How to get from Castellane to Nice
From Castellane - Place Marcel Sauvaire bus to Nice - Gare Routière Vauban. 1 h 44 min 17€. From Castellane - Place Marcel Sauvaire bus to Grasse - Gare Routière, walk to Grasse, then train to Nice Ville. 2 h 44 min 24€. From Castellane drive to Nice. 1 h 26 min 12€.