This will challenge the most dedicated geocachers. You'll need a boat to get to this cache, but it will be a beautiful ride there and neat scenery once you get there. You will find this cache at the old abandoned lighthouse at Port Eads. Once you get there, take the steps to the first level. You will see the doorway that goes inside the lighthouse. As you step through the doorway, look down. The cache is a magnetic key holder under that lip that you step through to get inside...right at the bottom of the doorway. Log only. BYOP. Please hide back as well...or better if you think necessary. You won't have to worry about muggles down there, so take your time and enjoy yourself. If you'd like, you can make your way to the top of the lighthouse and observe the mouth of the mighty Mississippi River and the Gulf of Mexico. Some local friends will be helping me take care of the cache.
Due to construction, I had to move from the original location. It's still a great location. You'll enjoy the trip there and the scenery once you arrive. Plan to take a few minutes and explore what all is there. This is a fishing community, so look for the fishing line.