The protest was aimed at denouncing the repeated refusal of Prime Minister Benjamin Netanyahu to dismantle Jewish settlements and agree to a pullout from the Jordan Valley.
The protesters arrived by bus and car and paraded a banner proclaiming "No peace with settlements," signed by the Youth Against Settlements group.
They brought generators with them, indicating that they plan to at least stay overnight.
Israeli police and soldiers deployed in the area, but made no immediate move to disperse the protest.
In March last year, 200 Palestinian activists set up a protest camp on the site of a Jewish settlement that had been under construction, as US President Barack Obama visited Israel.
Israeli police drove them out after several days of protest.
The United States has led a new push for Middle East peace since July, talking with all interested parties even as Israel and the Palestinians trade barbs, especially over Israeli plans for new settlements in the West Bank.