For many years the inseparable twin of Al Ain, in the United Arab Emirates, Buraimi is now divided from its alter-ego by a large barbed-wire fence. This shouldn’t be interpreted as a cooling of relations between Oman and its neighbour, just an attempt to sort out a border that leaked in both directions.
There's no public transport currently offered from Buraimi to Al Ain. Check insurance details with car-hire agencies if attempting to drive a hired car through this border – the rules change frequently.
If you visit Buraimi, take your passport with you: you cannot pass through the border post (which is currently in Wadi Al Jizzi – 50km before the UAE border) without it. The border is in the process of being moved to a more obvious position between Buraimi and Al Ain.