The Park is actually split in two. The story of the San Francisco's maritime industry is told in the visitor center. Like most NPS visitor centers the exhibits were well designed and informative. Another admission: Meh. I learned a lot, but it didn't get me going.

At least not until we saw the First Order fresnel lens a decomissioned lighthouse. I always thought a lighthouse lens was pretty much just a magnifying glass. It would be pretty much the same as when I focus the sun's light to start a fire. However, the fresnel lens was far more complex. It's a series of lenses that seemed to flash as it rotated slowly. There was some diffraction, too, as the light was split into its different colors.

Across the street from the visitor center is a wharf extending into the Bay. Like the visitor center, it's free to walk out and see some of the ships and a few more exhibits. However, to go on the ships requires an entry fee or a National Park pass. Since we had the latter we boarded first the old sailing ship and then the Hercules, and old tug.

On the sailing ship we were limited to the deck so it wasn't that interesting. (A more interesting sailing ship experience was the USS Constitution in Boston.) Although there was no one else aboard, the doors were open on the Hercules so we explored it thoroughly. The engine room was massive, but the crew quarters were tiny. Whenever this was in use the people must have been much shorter because we had to duck through every hatch. The only thing the Hercules needed was more signage telling us what the various rooms were used for and some of its history.

(We also walked through the old ferry (one of the first car ferries), but we've got plenty of experience on those types of ships back home.)

Of course, no NPS visit is really complete without some form of wildlife so we were thrilled to see a couple of sea lions going at it in the water. What surprised me most was that there were people swimming there even though (a) it was freakishly cold and (b) hello... it's called a sea lion. I bet it eats people.

Even though the San Francisco Maritime National Historical Park was more of an if-we-have-time than a must-see part of our itinerary I'm glad we had a chance to visit. The Hercules was well worth the cost of admission. Just remember you need to say the name like Eddie Murphy would. "Hercules! Hercules! Hercules!"

(And why are they called "ships" rather than "boats?" Because a ship has boats (e.g., lifeboats), but a boat doesn't have ships. The More You Know)