Saur Mohyla is a WWII monument built on a strategic hill where a lot of intense fighting happened between the Red Army and the Nazi Army. Today, control of this hill separates the Donetsk People’s Republic from the Luhansk People’s Republic (and the Russian border). It has changed hands several times.

Photos of the monument, which has been destroyed by artillery fire:
http://censor.net.ua/photo_news/297402/25ya_vozdushnodesantnaya_brigada_na_otbitoyi_u_rossiyiskogo_spetsnaza_saurmogile_fotoreportaj

Photos of the rallies the Yanukovych government used to hold there:
http://www.62.ua/news/376353