Hours before thousands of worshipers descended on the tomb of Rabbi Shimon Bar Yochai for the annual Lag Ba'omer celebration last night, two Arab construction workers were still hard at work applying the final touches to a tunnel underneath the Meron junction.

The laborers, from the northern town of Shfaram, were putting up a barrier that would separate men and women as they emerged from the tunnel.

"You can't mix meat and milk," one of them joked, referring to the Jewish dietary laws that bar meat and dairy products from being consumed together.

Every year, tens of thousands of observant Jews flock to Bar Yochai's tomb in the Upper Galilee for Lag Ba'omer, which, according to Jewish tradition, is the anniversary of the rabbi's death. Last year, the state comptroller criticized state authorities for poor organization at the mass gathering, leading to radical changes this year.

"They even provided soap for the bathroom sinks," a Magen David Adom medic who attended the gathering yesterday said.

The new tunnel, meant to facilitate access to the site, was one change. In addition, makeshift huts and illegal structures that covered the area last year were cleared, and some 4,000 police officers took up key positions to prevent overcrowding.

Finally, a complete ban was imposed on private cars entering the Mount Meron area, despite attempts by prominent community members to obtain special permits for their vehicles. Dozens of buses offered worshipers free transport to the site from three different car parks nearby.

"It's free transportation at the government's expense," a child from central Israel told his father in astonishment. "Don't worry, the government's taking this out of our pockets," his father replied.

"This is the 78th celebration I am attending," said Rabbi Menashe Eichler as he stood at the entrance to the tomb, the second most visited Jewish holy site in Israel, after the Western Wall. "I missed only one, back in 1948."

Today, the site attracts one million visitors annually. But Eichler recalls a time when even Lag Ba'omer, the peak day for visitors, brought out only 2,000 people. The elderly rabbi, who was once a member of the Stern Gang - a pre-state Jewish underground group that fought the British and the Arabs - said he used to rent a mattress from local Arabs and sleep outside under a thin canopy when he came for the celebration. In the morning, he would feast on a breakfast of eggs and tomatoes before setting off for the tomb.

Nowadays, the area is covered with bed-and-breakfasts that offer worshipers more comfortable accommodations. Celebrants will begin leaving the area today after a night of singing and dancing around bonfires, which are part of the traditional festivities.