I would have opted for 'are' too, but the writer has the choice--s/he is evidently thinking of ' breathtaking views, gorgeous food, and arts and crafts ' as a single grand experience. This is an independent clause: ' , but also on offer is breathtaking views, gorgeous food, and arts and crafts. ' The S and V are inverted; here is the more common word order: but BVs, GF and A&C are also on offer.
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