Narva Castle (and Russia border crossing)

Set just above the border crossing bridge, and facing Ivangorod Castle across the Narva river, this medieval fortress marked the eastern reach of the Swedish Empire, the place where Europe ended and Russia began.

The grounds are free to enter, the tower contains a museum and requires a ticket. The grounds also contain the only statue of Lenin left standing anywhere in Estonia - turned to point eastwards. North of the castle grounds are the remains of old military ramparts, but don't expect to see much - other than the castle and the (unrenovated, closed) Town Hall building, the historic center of Narva was destroyed in heavy fighting in WWII. (If you have more time to kill in Narva, point your GPS to the Kreenholm factory area.)

The waterfront promenade on the Estonian side will take you down past the river's bend to a point where you can take a famous photo of the two castles together - the vertical Swedish keep on the west bank and the squat Russian fort on the east.

The bridge is the only vehicle crossing point into Russia north of Lake Peipsi; although often traffic-congested, motorcycles actually have priority and can usually skip the queue - but you still have to go to the holding area outside of town first.