The Bornplatz Synagogue, a neo-Romanesque, 1,200-seat sanctuary that was once the largest synagogue in northern Germany, was burned down on Kristallnacht in 1938.
More than 40 Sinai Temple members, including several rabbis, took a two-weeks tour throughout Israel.
The Old Synagogue dates back to the 1090s, when its first stones were laid.
Bomb threats have been plaguing synagogues in the US since the summer, but all the threats on Rosh Hashanah were deemed not credible.
Weingarten’s Synagogue Neustadt is housed in a refurbished, mid-19th century train station main hall.