I did this trip back in May and forgot about writing it up until now.
Cattle Point Road is asphalt concrete, so it’s not smooth. I made the mistake of inflating my tires at the start of the ride – it might be better with softer tires or shocks. On the plus side, unlike cement there are no pebbles or pot holes on the side of the road to watch out for.
The trip down to San Juan Island National Historical Park is rolling hills through farmland with no ocean views and no shade. Traffic was regular but every car gave cyclists a lot of room. I’ve heard there are enough cyclists on this road in the peak season that you need to pull off the road when you stop – there are some stretches without a lot of driveways.
The two-sided ocean view at San Juan Island National Historical Park is stunning. I’d recommend going up to the Redoubt and down to Grandmas Cove (foxes and otters and deer, oh my!). There is very little historical content: it’s more about playing on the beaches and wandering around the field. There are bike lock-ups and bicycles are not allowed on most trails in the park.
I’m pretty fit and found the trip reasonable but not easy on a fixed gear bike except for a long, gradual hill by Jakles Lagoon. The shortcut from the American Camp to Pickett’s Lane is a gravel road full of potholes that is extremely unsuitable for cycling.
By the time we got to Cattle Point we didn’t have time to visit the lighthouse. The beach at Cattle Point is kind of boring, so I’d suggest visiting Fourth of July Beach if you’re short for time.