Attention fort fans: Vladivostok teems with sprawling, rather unique subterranean forts built between the late 19th and early 20th century to ward off potential Japanese (or American) attacks. Sixteen protective forts (including four on Russky Island) and hundreds of artillery batteries and other military objects encircle Vladivostok. Many buses pass here (like No 107 from the train station); get off at 'Akademicheskaya' stop (one after 'Zarya'), and walk 20 minutes east on the road leading up the hill (you may have to ask directions).
The best to visit is the hilltop Fort No 7, 14km north of the centre. It has 1.5km of tunnels, pretty much untouched since the last 400 soldiers stationed here left in 1923, although the NKVD later used it as an execution chamber. Views are good too. This and other forts can be visited on a tour with Vladivostok Digger Club or with Lotos Co.
