St Mark's NWR certainly makes it into my top ten places to go in Florida. The combination of the Gulf, the marsh, the pristine areas of pine forest guarantees there will always be something worth watching. The lighthouse is not open to the public but is easily approached. There are many vantage points to get great images regardless of the time of day or weather. There are some old pilings left from a dock that is almost always full of pelicans, cormorants and assorted other birds. I recommend you spend a day there, take a picnic because once you are on the NWR you are a long drive from lunch.