I spent 15 hours on a luxury train with only a backpack. Here are 5 items I'm glad I packed and 6 things I wish I had with me.

On May 15, I arrived at Denver's downtown train station. The breezy morning and saturated blue skies seemed like an ideal day for a train ride.

But I wasn't about to board just any train; I was riding the Rocky Mountaineer, which has earned a reputation as one of the most luxurious trains in the world.

The Canadian train company operates four routes, three of which are in western Canada. The fourth — and newest — route is the brand's first US route, which takes passengers from Denver to Moab, Utah, with an overnight stop at a hotel in Glenwood Springs, Colorado.

The trips range in price, and its bottom-tier tickets cost anywhere from $1,465 to $2,342. I booked the US route on sale and snagged my $1,465 ticket for $1,052. Insider paid for the trip, per our reporting standards.

In the welcome materials sent a few days before my trip, the Rocky Mountaineer team informed me that I wouldn't have access to my suitcase. Instead, the company recommends "you bring a day pack or bag which is small enough to fit at your feet onboard the train as there is no overhead or under-seat storage."

I packed a backpack and a suitcase, and when I arrived at Union Station, I learned we would take a motorcoach bus to the train. As they loaded my suitcase into the underneath storage of the bus, I missed the memo that I was saying farewell to my bag.

I thought I'd have access to it again once the bus dropped us off. I was wrong, and as I boarded my glass-dome train car, I crossed my fingers and hoped I had everything I'd need for the nine-hour ride.

While I had almost everything I needed already packed in my backpack, there were a few key items I wish I could have taken out of my suitcase — or packed in the first place.

It was warm in Denver when I left, and I knew I was only heading toward hotter temps.

In Moab, the forecast predicted temperatures of nearly 90 degrees Fahrenheit. I was prepared to be hot.

But I also know hot outdoor temperatures often mean arctic air conditioning temperatures indoors.

As I left my apartment at 7 a.m. for the train, I luckily remembered to grab a jacket.

My prediction was spot on, and AC was blasting on the Rocky Mountaineer every moment of the trip. For the next two days, I rarely took the jacket off. Even donned in a thick, corduroy jacket, I was still cold for the majority of the trip.

On the Rocky Mountaineer, each train car had its own chef and train host, who helped serve food and functioned as tour guides for the two days.

The chef and host were always bouncing from one passenger to the next, refreshing drinks and delivering meals. But the only cups on the train were small, stemless wine glasses.

Meanwhile, I was heading to Moab, where I planned to spend the next two days exploring the crowded Arches National Park. With that in mind, I needed to stay hydrated, and a few small glasses of water weren't going to cut it.

Luckily, I brought my own water bottle. Each morning, I filled it up before boarding the train. When it was empty, the host refilled it, which seemed better than ushering her over every half hour for a small glass of water.

For the bulk of the trip, my phone had zero bars.

While I couldn't send texts or share updates, I did have my phone on me for both days.

The views on the train were incredible, and I found myself constantly opening my camera app to snap pictures.

The nonstop photographing drained my phone, so I was glad I packed my phone charger in my backpack instead of my suitcase.

The train also had convenient outlets located in the middle of each row of seats.

One of the Rocky Mountaineer's major appeals was the train's glass-dome windows.

Curving over the train car's roof, the windows provided nearly 180-degrees of sightseeing out into the expansive landscapes.

While the views were impressive, the windows also meant that there was no avoiding the sun. Around lunchtime, my sunglasses were a must as bright rays bounced throughout the train car.

As Moab's recognizable red sandstone mountains came into view, our train host and chef made the announcement that they'd be coming around the collect tips.

According to the Rocky Mountaineer, it's standard to tip between $45 and $55 depending on your service. I landed right in the middle and tipped my host and chef a collective $50.

While the train host said they accepted credit cards, it was quicker and easier to tip with cash, so I was glad I remembered to pack some before boarding the train.

The few respites of warmth were outside on the train's observation deck, which was a windowless section between train cars.

I loved standing out in the area, with my hair blowing in the window while rivers, mountains, canyons, and farm animals passed by.

But what I didn't love was how the wind dried out my eyes. By the end of the second day, the wind combined with the AC left my eyes irritated — something that could've been fixed if I had packed eye drops.

In the Rocky Mountaineer brochure provided onboard, one section highlighted the flora and fauna guests might see along the train route. As I read the descriptions of the animals, trees, and flowers I might spot along the train tracks, I laughed.

There was no way I'd be able to spot a Colorado columbine flower without a pair of binoculars.

A surprising amount of passengers had come prepared with a set of binoculars, and next time, I'll join them.

Sure, it was thrilling to spot a bald eagle and pronghorn in the distance, but it would've been even more exciting if I viewed them up close through binoculars.

As a solo traveler, I was thankful the group around me on the Rocky Mountaineer was social.

Instead of filling my time by reading a book or watching movies, I chatted with my nearby seatmates.

And although I was never bored, I think it would've been smart to pack a deck of cards. The cards could've filled my time during the train delays and kept me socializing with passengers throughout the trip.

Similar to how my sunglasses came in handy, a hat would've also been helpful. Unfortunately, I left it packed in my checked bag.

With a hat, I could've protected my face from the sun and been able to see the passing landscapes without viewing them through tinted sunglasses.

Even with my corduroy jacket, I was still freezing for the bulk of my train journey.

As I disembarked the train for the final time, I noticed a passenger left behind a thin airplane-like blanket, and I realized a bit too late that the Rocky Mountaineer team had blankets passengers could use.

But even then, I'm not sure the thin blanket would've helped much. For my next train ride, I'll be packing my own fluffy blanket to keep me warm.

We disembarked from the train in Glenwood Springs at 6 p.m., and I immediately felt a time crunch. In just two and a half hours, the sun would set, and the town's restaurants and attractions would start to close.

I wanted to take a dip in the town's famous hot springs, but unfortunately, my swimsuit and clothes were already at Hotel Colorado, where some passengers spend the night.

It would've been smart to plan ahead by packing my swimsuit in my backpack. That way, I could've spent more daylight hours at the hot springs, instead of changing at my hotel room.

Even if I didn't need a swimsuit, I still think a change of clothes would've been smart to pack. After spending nine plus hours on the train, it was refreshing to wear a set of clean clothes.

Sure, my packing list needed a few tweaks, but overall a single backpack fit everything I needed for 15 hours on a train.