I would add to Captain Arnold’s recommendations below for cruising Charleston Inlet and Harbor (apparently he is speaking about nighttime passage of these waters), to have a well functioning and very visable GPS chartplotter aboard. There are so many lighted aids to navigation in Charleston Harbor, it’s very easy to become confused. And, there has been more than one tragedy in these waters from vessels trying to navigate after dark.
Personally, we never cruise these waters at night. If you choose to do so anyway, please proceed with the greatest of caution!

Charleston Bay area generally is notorious for shifting shoals, low depths at low tide. Keep very carefully to main channel markers and particularly if entering Shems Creek or at the top entrance to the ICW – can’t tell you how many boats I’ve seen stuck there – even small center cockpit fishers drawing only 2ft. (At one time one of them was me 🙂 And for sure stay clear of the “jetties” and go either side of them through the green and red markers. When approaching Charleston in the main channel (to starboard coming in) which the big ships use, you can see a spotlight on one of the downtown buildings and aim for that always keeping it in sight (if you stray out of the channel the light in effect dissapears)
Best wishes
Arnold