Not toys. Memories.

The dining room and the children are gone. A train room and nostalgia have taken their place.

Adults are now the toy industry's best customers. Adult-only households reportedly accounted for the majority of U.S. toy sales this summer, according to The New Yorker. Experts call it "kidulting."

I get it.

My Uncle Allen had a sprawling train layout in his basement. It was the biggest, most fabulous thing my young eyes had ever seen. A real world in miniature. He kindled a passion. I built my own on a 4-by-8 board in a corner of our living room. N scale. Small trains, big imagination.

In my late 20s and 30s, I started collecting Department 56 houses for Christmas. New England Village. Christmas in the City. I bought the ones that tugged at something from childhood. Every December, they came out of their bins.

Then Trey and Sarah got older. Real life got busy. Fewer houses made it out each year. By the end, only two churches and a manger scene remained. I have a thing for lighthouses, so a trio of D56's finest stood sentry, a 365 safe harbor on bookshelves flanking the fireplace.

The houses deserved better. A permanent home, with a train or two carrying passengers and freight to give them purpose. Quick research led me to On30—O-scale trains riding on HO track. One 4-by-8 board became two, united by a 34-inch tie that binds. A display became a layout.

Every building was chosen for a memory. There's a city that brings to life the thrill of weekend trips to NYC: museums, Central Park, Broadway shows. There's Maryland countryside, complete with a fox hunt and the Maryland Hunt Cup, a spring tradition where I watched Ben Nevis win back-to-back in 1977 and '78. There's a New England corner where a naval academy and a few shops stand in for old Annapolis and St. Michaels, harbor towns that held their ground while the world around them changed.

Most of what the trend sells is finished. Take it off the shelf. Put it on a shelf. This isn't that. I'm building a whole village. An homage to a Maryland I left and never stopped missing.

The goal is a train running by Christmas. I hope Uncle Allen approves.

—JR Ball