My train left at 11:13 p.m., so after checking out of my hotel at midday, I went and found a place to store my luggage in the city.

I also had hours to kill before boarding, so I visited the Senate Square Christmas Market, Temppeliaukio Church, and the Allas Sea Pool — working up a sweat in saunas then jumping in freezing water.

However, I later learned that many of Helsinki's hotels offer a late-night checkout package for these late-night trains. I don't regret my afternoon in the city, but others might prefer a quick power nap before the overnight journey.

My seat was about 47 euros, but the ability to book neighboring seats at a reduced rate was a game changer.

I added the 21-euro upgrade on a whim, but it really improved my experience. At 5-foot-3, I comfortably curled across two carpeted seats and managed to get some shut-eye.

Because I was traveling during peak season, all the carriages were booked. If I hadn't reserved the seat next to me, I would've been sleeping upright like a sardine with a neighbor.

I felt pretty smug being horizontal.

The biggest kicker was the conductor's insistence on keeping the carriage lights on overnight, apparently to prevent pickpocketing.

I get the gist of the strategy, but I'm actually not sure how effective it was for that purpose — everyone just covered their faces with their coats instead.

I'd undertaken a similar rail journey in Sweden last year and slept like a baby in the darkened passenger cabin. The low lighting even allowed me to spot the northern lights from the window. On the Santa Express? No such luck.

Sleeping with the lights on was much harder. In hindsight, I should've brought an eye mask or invested in a private cabin (40 to 160 euros) where I could control the light switch.

I'd been worried about food quality on the train, so I hurriedly ate before boarding.

In hindsight, I didn't need to scarf down an 11 p.m. dinner. The train's restaurant car had an impressively varied menu.

Food service stayed open for dinner until 2 a.m. and reopened for breakfast at 4 a.m. There was a mixture of refrigerated sandwiches, pizzas, pastries, and alcoholic, hot, or soft drinks.

Around an hour into the journey, both my mobile data and the train's complimentary WiFi stopped working.

I'd read other travelers' online reviews, and many people said that this would happen, but I hadn't expected it so early on in the trip, especially since we were still riding past fairly built-up suburbs.

Fortunately, I'd prepared for a digital detox and was carrying a pen and paper to jot down story ideas. Old school? Yes, but I have to admit it really amplified the feeling of adventure.

I'm happy that I snapped a picture of the toilets while boarding, as they looked pretty messy within two hours. It was a shame, as the decor and skylights were quite pretty.

On reflection, the situation wasn't helped by the small sinks — water splattered everywhere with each use of the tap.

Throughout the trip, they were usable but unappealing enough to make you think twice about drinking a coffee too fast.

My ride on the Santa Express was sadly Santa-free aside from the large illustrations adorning the carriage exteriors.

There was no festive dress-up or meet-and-greet on board, but the platform was magical nonetheless.

Carol singers erupted with Christmas songs, and barrier staff exchanged secret grins before allowing floods of giddy families onto the platform in festive Rovaniemi.

The excitement was infectious as I headed toward Santa Claus Village and the remainder of my trip in Lapland.