Forgot to add that there are some excellent restaurants in Vilnius.  I recommend Lokys for its venison stew; Pilies; Stikliai; and Leiciai.  
In Vilnius, I would recommend visiting the Jewish Holocaust Museum and Jewish Tolerance Center, the Synagogue, the excavation at the  site of Vilna Great Synagogue & Shulhoyf, Zydu Street, behind school the Russians built to cover the ruins of of synagogue (I think the school has been torn down since we were there as the excavation has expanded).   Outside of Vilnius - Trakai castle and Kariates Synagogue and Museum are interesting.  The memorials at Ponar are extremely moving.  In Kaunus - the Blue Synagogue, and  the house of Chiune Sugihara who issued transit visas saving 2,300 Jews. On route, stop in village of ZIEZMARIAI to see one of few remaining wooden synagogues in Lithuania that has been partially restored, and the IX Fort. 

Susan Gray, Chicago
Searching:

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