The practice of recording oral histories is hugely valuable. But when the testimony is compiled in an epic propaganda film like “Route 181 — Fragments of a Journey in Palestine-Israel,” it loses a large portion of its potential audience.

“Route 181” aims to illustrate the old adage that it’s the winners who write history and that memory is conveniently selective. That’s a worthy goal, but the filmmakers’ zeal in including every negative comment anybody — Arab or Jew — has to say about Israel, gives the film an unmistakable slant.

Israeli filmmaker Eyal Sivan, who’s worked in France since 1985, and Palestinian director Michel Khleifi hit on the idea of shooting a documentary together along the border adopted in U.N. Resolution 181, the document that partitioned the Palestinian Mandate into Jewish and Arab states.

As it turned out, the U.N. demarcation never existed anywhere but on paper. The 1948 war between Jews and Arabs that culminated in Israel’s independence ended with the Jewish state holding more land than the U.N. had allotted.

“Route 181 — Fragments of a Journey in Palestine-Israel” screens Friday, April 23, and Saturday, April 24, at the San Francisco International Film Festival. Both filmmakers are scheduled to attend.

Khleifi (who moved to Belgium in 1971 and directed the terrific 1987 feature “Wedding in Galilee”) and Sivan drive north from Ashdod to the Lebanese border, interviewing ordinary people in lieu of the historians, journalists and politicians who crop up in other films on the Israeli-Palestinian conflict.

The filmmakers provide ample time for most of their subjects to tell their stories. With a 4 1/2-hour running time, “Route 181” is intended to stand as a historical document as well as a current events piece.

It’s not an accident that Sivan and Khleifi focus almost exclusively on individuals of middle age and beyond — in other words, people who experienced firsthand the events of ’48 and their aftermath, or whose parents did. Sivan and Khleifi speak with both Jews and Arabs along the way.

The elderly Jews recall the land purchases and military tactics that resulted in the pre-1967 transfer of Arab lands to Jewish ownership. One otherwise likable man suggests that if the Jews had done to the Arabs in 1948 what Americans did to the Indians in the 19th century, Israel would have one less problem today.

Meanwhile, the Arabs recall the names of the Palestinian villages that were demolished or renamed by Israelis. They are prodded by the filmmakers, who never miss a chance to expose an injustice committed by the state of Israel or its Jewish citizens.

Indeed, “Route 181” displays an obsession with the land that seems downright anachronistic. The most candid and revealing sequences, therefore, are those squarely addressing the dilemmas of the present. (Among them: The filmmakers visit a barbed-wire factory whose future seemed threatened by the peace process; today, however, business is booming.)

In the south, posters abound with the slogan “The Palestinian state is Jordan. Transfer = Peace and Security.” For a couple of sobering minutes, as they speed down an empty new highway north of Jerusalem, the filmmakers shoot the new barrier erected to separate Arabs from Jews.

An assault by soldiers on a peaceful joint Israeli-Arab demonstration in Tulkarem is unexpected and shocking. On a lighter note, a soldier at a checkpoint shows off her pierced tongue for the camera.

For those willing to confront it, “Route 181” offers a painful look at Israel’s past and present. Its value would be immeasurably greater, however, had the filmmakers stowed their agenda in the trunk before they headed out on the road.

“Route 181 — Fragments of a Journey in Palestine-Israel” screens at 1:30 p.m. Friday, April 23, at the Pacific Film Archive, 2625 Durant Ave., Berkeley, and 3 p.m. Saturday, April 24 ,at the AMC Kabuki 8 Theatres, 1881 Post St., S.F.. Tickets: $7.50-$12. Information: (925) 866-9559 or www.sffs.org.

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