Reid recommended visiting Veliko Târnovo, an ancient capital, and the picturesque city of Plovdiv, home to Roman ruins.

Reid建议（我们）参观 Veliko Târnovo，这是一座古老的首都，还有风景如画的普罗夫迪夫，罗马遗迹之源。

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Some 57km over the mountains from Shipka lies yet another historic settlement - Veliko Tarnovo, the "City of the Tsars" - famous for being the medieval seat of Bulgarian power.

BBC: Bulgarian road trip: Sofia to the City of the Tsars