Rothesay's most unlikely attraction is a public convenience. The gents' toilets by the ferry terminal are a lavish Victorian period piece — a shrine to ablutions, with the original ornate fittings — and still in working order for a small fee.
There is no viewing gallery, so this is a place to use rather than tour; tourists who pop in for photographs should be considerate of the men using it for its intended purpose. The ladies' facilities next door are modern and much less interesting.