I’m looking for a bike to take my surfboard (6’6”) to local surf breaks. I would be biking 1-4 miles on a concrete or asphalt beach path that gets some sand on it. What’s a good bike for this purpose? Hybrid? Beach Cruiser? Fat?
The problem is that salt water destroys bikes. It's why beach cruisers are as cheap and simple as possible, if they actually get used by the ocean they will either require washing or rust out in a year or so.
A Fat bike would be a really good choice if riding on the beach itself is part of your plans. You can't really ride a beach cruiser in deep soft sand. However, fat bikes are more expensive and you'll need to be diligent about washing the bike if you want to keep your investment. Theft is also an issue, fat bikes are more likely to be stolen than a cheap rusty beach cruiser.