Hi Stephanie
There are two lighthouses at Mayport. The St John's Light Station and the St John's River Light. Both are Accessible through the Base. The St John’s River Light is at the edge of the base, at the far end of an airfield and can be viewed from outside the base. I haven’t seen the new Museum but I have been told that it is just outside the Base. That would be at the road next to the ferry.
Daniel