Rabbi Jonathan Wittenberg and his dog Mitzpah will be doing a sponsored walk from Frankfurt to Finchley.
The trek is in support of Tikkun Olam – repairing and helping the rest of the world.
The New North London Synagogue rabbi will be raising money to construct libraries in the Galilee, in Northern Israel, and in Malawi.
Donations will also go to a Jewish community centre in the Ukraine and to a mentoring programme to help young people develop social enterprise projects.
The pair plan to cover 250 miles by foot and use public transport for the rest of the distance.
The journey, which begins on October 13, will take them along the Main and Rhine rivers, passing through towns and places of Jewish history in Germany and Holland, before taking the ferry back to Britain.
Rabbi Wittenberg said he is aiming to ponder the achievements and tragedies of a thousand years of Jewish life. He plans to meet Jewish, Christian and Muslim leaders and communities along the way.
The trip is also a tribute to his grandfather, Dr Georg Salzberger, who served as a rabbi at Westend synagogue in Frankfurt.
The interior of the building was destroyed during the Nazi’s Kristallnacht attack in November 1938.
Rabbi Wittenberg said: “From Mainz to Cologne my route follows the path of the first crusade of 1096.
“Testament to the Holocaust will be everywhere”.