Chattanooga — "All aboard," my 11-year-old hangs off the train and shouts to his siblings. "All aboard who's coming aboard."

But this train isn't going anywhere. It's one of 24 train cars parked on the grounds of the Chattanooga Choo-Choo, a Holiday Inn hotel converted from the Terminal Station train depot.

Chattanooga Choo-Choo (ENLARGE)

The gardens at the Chattanooga Choo-Choo features trolley car rides, shopping and places to eat.

(ENLARGE)

When you get tired of sightseeing, spend the night in a train car at the Chattanooga Choo-Choo.

RELATED LINKS: • Photos of Chattanooga • Southeastern festivals through June • A guide to Southeastern theme, water parks • More places to go in Southeast

You enter one of the 48 train rooms as if you're walking up into a real train. Because you are. The overhead racks are still there, but the seats have been removed and the spacious rooms are furnished with queen-sized beds. Some of the rooms also have trundle beds that open to two twin beds, easily accommodating four people. Bathrooms have been added to each train room.

The train cars are cleverly parked in sets of double rows, so when you look out your windows, you see another train. When you disembark from your room, you feel like you are in a train station. I traveled with a 5-year-old, a 9-year-old and the 11-year-old and everyone was enchanted. And that was before we went swimming in the indoor pool or had pizza in the train car that was converted to a pizza parlor.

The terminal's dome room is now a dining hall, with food and prices geared toward families. We had breakfast there one morning, and dinner another.

The area that once housed the baggage room is the Station House, a more upscale restaurant with singing waiters and waitresses. You can also have a fancy meal at Dinner in the Diner on Friday and Saturday nights when a dining car is opened as a "fine dining" restaurant. I got that description from the desk clerk and took it to mean, "We don't recommend it for kids."

A trolley car travels the tracks behind the station for $1 per ride, and shops line the gardens in the former rail concourse. You can buy ice cream, coffee and other treats and just enjoy the grounds. Three other hotel buildings on the 24-acre site offer traditional guest rooms and convention rooms.

We checked into our rooms at 3 p.m. and didn't leave the grounds until the next morning. With one indoor pool and two outdoor pools and a hot tub, no one was bored and that says a lot when you are with three kids. But the best part really was hanging out in the cozy train before bed, watching TV and then going to sleep.

A free electric public bus goes from the Choo-Choo to the riverfront downtown and Tennessee Aquarium about every 10 minutes.

One of the aquarium's best features is the way it maximizes its fabulous location on the river. The main exhibits are divided into two buildings: the River and the Ocean. You can do one building, and then take a nice break on the river or at one of the many restaurants in the complex, before you go to the other building. You can go back and forth all day.

There's a playground right on the river, and a water taxi that takes you to the famous carousel on the other side of the river.

We all liked the exhibits. The penguins are new and fun to watch. The otters are lively. The buildings and tanks are well-designed. We especially liked a trout exhibit that shows about two dozen trout attempting to swim upstream. Water rushing at the fish gives them the illusion they are making progress, but they swim in place stoically. Every once in a while, one gives up and moves to the back of the line. It was a good lesson on instinct and perseverance.

"Kind of like middle school," my sixth-grader said.

We also enjoyed the touch tank. On display when we were there were stingrays (they feel like rubber) with the barbs removed (they grow back) and small tiger sharks.

As exciting as it was, though, to touch a stingray (very), there were no complaints when it was time to go back to the train. As I closed the blinds on the windows as the sun set, I really felt like we were moving along the rails.

IF YOU GO

Chattanooga Choo-Choo Holiday Inn, 1400 Market St. 423-266-5000, www.choochoo.com . Rooms in the train cars are $179 per night. Packages that include Aquarium and Imax tickets start at $219.

Tennessee Aquarium, One Broad St. 1-800-262-0695, www.tennesseeaquarium.com . The aquarium has just started offering a two-day Big Fish Pass. At $24.95 for adults and $17.50 for kids ages 3-12, this a good deal because regular admission is $19.95 for adults and $12.95 for kids. Buy the pass at the aquarium or online at www.tnaqua.org/visitorinfo/bigfishpass.asp . The pass includes: $2 off adult and $1 off child tickets at the IMAX Theater; 10 percent off aquarium and IMAX shops and concessions; $2 off tickets at Creative Discovery Museum, Ruby Falls and Rock City; buy one $5 adult ticket, get one free at the Water Taxi and Fat Cat Ferry; free child ticket with purchase of an adult ticket at Southern Belle Riverboat; buy one ticket, get one free at Hunter Museum of American Art, and 10 percent off at Blue Water Grille and Big River Grille & Brewing Works.

MORE TO SEE

A 10-minute drive from downtown is Lookout Mountain and three attractions: Rock City, Ruby Falls and the Incline Railway.

Only the most intrepid family would want to do all three in one day, though with summer hours to 8 p.m., it is possible.

We chose Rock City. It's a path up Lookout Mountain through gardens, rocks and mini-caves. From the top, you can see seven states (Georgia, Tennessee, Kentucky, North and South Carolina, Virginia and Alabama). There's an exciting swinging bridge and lots of great views.

The path is different on the way back, and it takes you through the famous (or infamous) Fairyland Caverns. In little caves in the mountain are ceramic sculptures of fairly tale creatures. Founder's Day is May 17, when the attraction celebrates its 76th anniversary with a music and dance party.

Ruby Falls is a nearly 1 mile-long walk through more of Lookout Mountain's caves, culminating with a big water fall. There's also another path to the top of Lookout Mountain there.

It takes about 10 minutes to ride the Incline Railway to a third spot on top of the mountain. You can walk from there to a Civil War battlefield a few blocks away.

The three attractions are minutes apart, all with free parking. We spent about three hours at Rock City, including lingering over lunch on the patio. Others I have spoken with have spent a similar amount of time at Ruby Falls, less on top of the mountain after getting off the Incline Railroad.

• Lookout Mountain, www.lookoutmountain.com

• www.seerockcity.com , 1-800-854-0675

• www.rubyfalls.com , 423-821-2544

• www.ridetheincline.com , 423-821-4224