"Please excuse my broken Arabic," our guide, Yehuda Yarin, tells the mixed group of Palestinians and Israelis who have come to Yad Vashem to learn more about the Holocaust. It's a three-day joint excursion - a Tiyul-Rihla, the words for "trip" in Hebrew and Arabic - to Acre, Haifa and Jerusalem.

Yarin, whose day job is to guide groups of Jews and Israelis in Poland, including to Auschwitz, has the distinction of being Yad Vashem's only Arabic-language guide. "I first studied Arabic many years ago, at high school. But, you know, at high school the level isn't very good," he tells me. Later he started learning colloquial Arabic.

When the new Yad Vashem - the world's largest Holocaust museum and Israel's second most popular tourist site - opened in 2005, the odd Arabic-speaking group would come to visit. Yarin would show them around.

Since then, Yarin has guided Palestinians, both from the West Bank and Israel, as well as visitors from countries further afield such as Egypt. "Some of them know nothing," he notes. "Some of them have never heard about the Holocaust. Some of them know the history. It depends."

Although Yarin says he doesn't know what his Arab visitors "think in their hearts," he is impressed by their interest and inquisitiveness. "I'm glad when they ask questions," he says.

With the help of Arabic-speaking Israelis and Hebrew-speaking Palestinians in the group, Yarin tries to convey the magnitude and mindlessness of the slaughter.

He says the Holocaust was unique among modern mass killings because it was completely ideological and not an extreme manifestation of a political conflict - over territory or competing nationalisms - as other attempted exterminations were. "The Jews were not the enemies of the German people and they represented no threat to Hitler," he explains.

Although in terms of Jewish history the Holocaust is unique, sadly, the 20th century was filled with genocides, classicides and other mass murders of defenseless groups.

Inside the museum's somber pyramid-shaped galleries, the Tiyul-Rihla group of seven Israelis and six Palestinians, who had come on this three-day excursion organized by volunteers and largely paid for by the participants, wandered through Nazism's hall of shame. They saw it all, including Hitler's rise, the Warsaw Ghetto and the death camps.

Familiar with this horrendous chapter in history, the Israelis followed the commentary and exhibits mostly in rapt silence. For the young Palestinians who were being exposed to the full extent of Nazi atrocities for the first time, their attempts to grasp the enormity led them to ply our guide with questions.

"If the Jews were so assimilated and successful, why did the Germans turn against them?"

"Was Einstein Jewish?"

"Why did the Jews believe the lies about the Nazi death camps?"

"Why didn't the Soviets help the Jews?"

"Why did the West refuse to take in the Jewish refugees and Holocaust survivors?"

The personal stories showcased in the museum gave the experience a human face that the Palestinians visibly appreciated, while the section dedicated to the Righteous Among the Nations elicited the interest of both sides. That section chronicles non-Jews who protected Jews - including Muslims in Bosnia, Albania, Tunisia, Morocco, Algeria and other countries.

The Arabic being spoken by members of the group drew curious glances from Israeli visitors, who seemed to be trying to figure out what we were about. The passersby included groups of young recruits to the Israel Defense Forces, apparently on motivational tours. They caused unarticulated yet visible stirrings of discomfort among the young Palestinians, whose only exposure to Israeli soldiers comes with the soldiers as agents of the occupation.

Although some in the group had been to Yad Vashem before, experiencing it with this unusual group was an eye-opener. "It's important to see something you think you know well through someone else's eyes," says Dara Frank, 22, an American-Israeli student working on a master's in international relations at the Hebrew University. It makes you "start questioning what you think you already know."

Another visitor is Mohammed Mahareeq, 23. He is originally from Hebron but works at a hotel in Ramallah and volunteers with the Palestinian Red Crescent.

"When it comes to the Holocaust, we only learn the basics about it at school, that Hitler slaughtered the Jews, so this trip has helped us acquire a lot of extra knowledge," he says.

The idea that Palestinians study the Holocaust at school, visit Yad Vashem and display genuine interest in the tragedy is likely to come as a surprise to many Israelis who regularly see media reports about Arab and Muslim Holocaust denial.

One recent example was Hamas' angry response following the visit to Auschwitz by Ziad al-Bandak, a senior aide to Palestinian President Mahmoud Abbas. Describing the Holocaust as an "alleged tragedy," a Hamas spokesman said the visit was "unjustified and unhelpful."

The plight of one's enemy

Hamas' outburst, as well as the availability of literature questioning the Holocaust in some Arab countries, prove that there are Arabs who deny that this horrendous crime took place. But fixating on Holocaust deniers, as some segments of the Israeli media do, distorts the reality and plays down the importance of the work of people like al-Bandak, who has visited Auschwitz and expressed sympathy for the plight of his people's enemy. And he did so during a period of heightened animosity and distrust between the two sides.

But he is not a lone wolf. Many Palestinians are aware of the historic tragedy that befell their Jewish neighbors, but are often muted in expressing their sympathy due to the bitterness of the conflict or out of a conviction that it will be used as a political weapon against them. "Many Palestinians feel that sympathizing too much with Israelis could lead to justification for the occupation," Sami Adwan, a professor of education at Bethlehem University, was once quoted by the BBC as saying.

But there are those who point out that mutual sympathy is essential to building trust and understanding between Israelis and Palestinians. Determined to act on this conviction, one eccentric Palestinian-Israeli opened his own tiny Holocaust museum in Nazareth and tours the West Bank raising awareness about this dark chapter.

"When Palestinians learn about the Holocaust, they will understand the Jewish people better and can begin to develop a shared history," Khaled Mahameed, the founder of the tiny museum he established with his own money, was quoted as saying.

And building understanding and compassion is exactly what the Tiyul-Rihla trip to Yad Vashem is about. "The idea behind the initiative is to expose each side to the other side's narrative, and to have a very deep conversation about it," explains Israeli journalist and activist Nir Boms, one of the idea's originators.

A similar view was voiced by Ibrahim Yassin, an activist and professional cook from East Jerusalem whose night job as a DJ is clear by his look.

"Personally, I think this trip is very interesting because it's breaking down the walls between us: Israelis and Palestinians," he says.

There have been three joint trips (two to Israel, one to the West Bank ), and the participants have brainstormed ideas for a fourth, to the Palestinian territories. The Palestinians seek to introduce the Israelis to the Nakba (the Catastrophe ), the term Palestinians use to describe perhaps the most defining trauma in their national experience: the exodus of up to three-quarters of Palestine's Arab population, most of whom were not allowed to return following Israel's declaration of independence in 1948.

They lament the absence of a museum chronicling this painful chapter of Palestinian history. Some Palestinians suggest that the Israelis join them on a trip to a refugee camp to give them deeper insight into contemporary life for many Palestinians.

"I want to introduce our Jewish friends to the suffering of the Palestinians .... Just as they told us about their suffering in detail from an Israeli perspective, I'd like them to hear all the details about our stories," reflects Mutasem Halawani, a student of business management from Jerusalem. "This helps build an exchange of ideas and tolerance."