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From Tiberias to Nazareth, bus 431
Leaves at 6:30, 7:40, 9:00, 9:45, 10:30, then hourly till 1730, 19:00, 20:15, journey time half an hour.
From Nazareth to Tiberias, bus 431
Leaves at 6:38, 7:18, 0:08, 9:08, 10:23, 11:08, then hourly till 17:08, 18:53, 20:23
No Saturday service
From Haifa to Nazareth, bus 331 or 332, every few minutes daily (Saturdays as well), journey time 45 minutes.
On weekdays they leave from various places in Haifa, but all of them stop at the “Checkpost”. Anyone in Haifa will tell you where that is; it’s known even in Hebrew as Checkpost. (It’s the junction of roads 4 and 75 on the southeast edge of Haifa, and the bus stop will be on road 75 after the junction in the direction of travel.)
On Saturdays all the buses depart from Palmer Square, which is in the central downtown area near the port, and they also stop at the Checkpost.