45 minutes to an hour

That’s about right. The Three Sisters Islands are small and connected by short bridges — you can walk all three in maybe 20 minutes if you’re booking it.

But you’re stopping for photos, so add another 15–20 minutes. Plus a few minutes to just stand there and look at the water. An hour is comfortable. 45 is possible if you’re efficient.

Don’t overthink it. It’s a pleasant stroll, not a hike. You’ll have plenty of time for lunch afterward.