What is there to see at Fort McHenry?

Outside the fence
This is the majority of the 43 acres and it costs nothing. Grass, paths, a seawall and an open view across the water, in a corner of Locust Point about three miles from the Inner Harbor. The visitor center is here and it is free to go in, as is the film. It is also open from 7:00 a.m., two hours before anything is being sold.
Inside the fence
The star fort and the outer battery. That is the fee area in full, and $15 for an adult aged 16 or over is what it costs; under-16s go in free. Cannon are part of what is on display there, and the question everybody asks about them is answered as honestly as I can manage on are the cannons real.
The statue question
A steady trickle of searches asks what statue stands in the park. I have not verified which monument or memorial that question refers to, and I am not going to name one on a guess. Ask at the visitor center, which is free to walk into, or check the National Park Service page for Fort McHenry before you go.
Do the outside first. Once you have seen the fort from the grass you will know whether you want the inside, and the register is not going anywhere.
What is not here
The flag. The original Star-Spangled Banner is at the Smithsonian’s National Museum of American History in Washington, DC, admission free, no tickets needed. That single fact reshapes more Baltimore itineraries than anything else on this site: the detail is here.
Seeing it from the water
The 45-minute Inner Harbor sightseeing cruise names Fort McHenry as a sight and passes it from the water, with no stop and no landing. None of it includes entry to the star fort. That is a National Park Service ticket, sold at the gate and nowhere else.
Frequently asked questions
What is there to see at Fort McHenry?
The star fort and outer battery inside the fee area, and outside it the grounds, paths, seawall and water views, plus the visitor center and the film, all of which are free.
What statue is at Fort McHenry?
We have not verified which monument this question refers to and will not guess. The visitor center is free to enter and can tell you, and the National Park Service publishes the site's own information.
Do you need a guide to see Fort McHenry?
No, and no bookable tour includes admission in any case. Entry to the star fort is a National Park Service ticket bought at the gate; the rest of the park is free to walk.