IF you insist on riding on rails-there MAY be a old clapped-out train by Serbije Voz from some place north of border (Nis most likely) to Bgr-taking double time of bus. Local fares for trains are so low its a waste to spend a passday for that.
And the fun is not yet over: as from Bgr onward-to HU or to HR (HRvatska=croatia) also NO trains over the border.
Best site, pro rail, for this ; seat61.com
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