Smolensk — the region's capital is one of the oldest cities of Russia (9th century) and home to examples of 12th century architecture, a large kremlin, and a particularly important Cathedral of the Assumption; the historic center was rebuilt after the destructive Battle of Smolensk in WWII
Dorogobuzh — an ancient town, worth a visit for nearby monasteries and churches
Vyazma — a small city with a long history, largely rebuilt after the German occupation in WWII, home to the stunning three-tented Hodegetria Church, as well as numerous baroque churches, a monastery, and city cathedral
Smolensk Oblast is home to some of Russia's oldest cities. It is also the site of much of the most fierce warfare Russia has experienced, from the Mongol conquest, to Medieval wars for supremacy between Russia, Poland, and Lithuania, to the Napoleonic Invasion, to the two World Wars of the 20th century. Few original structures have survived these centuries of conflict, but Russia has faithfully rebuilt the most important of Smolensk Oblast's cultural monuments. The capital, Smolensk, is a major tourist destination in its own right, and is a convenient hub for exploring the region.
You should expect that few residents of Smolensk Oblast have anything greater than a rudimentary command of any languages other than Russian.
Smolensk is a short (by Russian standards) train ride away from Moscow and a fairly easy trip from Saint Petersburg. No major airlines fly into Smolensk airport (LNX).
Nearby Pskov Oblast is a similar destination—a historic borderland region—that makes a fine complement to Smolensk travel. Trains also depart from Smolensk to Minsk, Belarus.