Translation:The safest road is that one on the left.
Since più can mean 'more' why is not 'the street on the left is safer' acceptable ie comparative rather than superlative adjective.
(American English speaker) I think it's the "la" that makes it superlative, even though it's not right in front of "piu." But I'm not sure
and because there isn't the "than" a noun that the comparative should have (just like english): "più" + adjective + "di". for example "questa strada é più sicura di quella" (this road is safer than that one)
I wonder about this too, why is one version of the comparative and the superlative accepted as the correct translation? I interpreted this sentence with "safer"
Because "la strada piu' sicura" is a closed structure that keeps together, and the e' refers to this. As far as I know. :)
It accepted "the safer road is the one on the left" but it can be formulated in different ways in English, like "the safer(or safest) road is on the left" which means the same thing