The first two capitals are rather obvious, but the third one is very tricky because it is not really named after Sofia, the capital of Bulgaria - it is part of the first name theme in downtown Helsinki. Therefore the careful wording alias to a capital, not named after a capital.
I didn't consider Tallinnanaukio (Tallinn Plaza) for a street here.
Mannerheimintie is the big boulevard from downtown Helsinki northwest. Lots of streets meet it, but just one of them goes accross without changing name. That's Nordenskiöldinkatu.
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