TrainTastic, operated by the Mississippi Coast Model Railroad Museum, occupies a 50,000-square-foot (4,645 m2) building at 615 Pass Road in Gulfport, Mississippi, and bills itself as the largest model railroad museum in the world. The attraction grew out of a local model-railroad club: the collection dates back to 1990 and the Train Club was formally organized in 1993, expanding through a series of adjacent buildings on Pass Road before reopening in its current, greatly enlarged home in June 2023 under the TrainTastic name. Brothers Richard P. Mueller, Jr. and Glenn Mueller, Sr. — the family behind RPM Pizza, the region's Domino's master franchise — funded the expansion as a philanthropic project rooted in a childhood collection that began with a single Lionel train.

Inside, more than twenty-five elaborate layouts run trains in scales from Z gauge up to G gauge, and the museum presents close to 200 years of railroad and model-railroad history, including a model train that honors POW-MIAs of Vietnam and World War II. A centerpiece Gulf Coast layout recreates local landmarks — from Keesler Air Force Base and the nearby Mississippi Aquarium to Café du Monde in New Orleans's French Quarter — using 3D-printed miniature buildings; the museum values that single display at more than one million dollars. Three of the layouts are built entirely from LEGO bricks, part of a collection of nearly two million pieces that TrainTastic promotes as the largest LEGO railroad display in the region.

Beyond the layouts, visitors enter through a full-size passenger car themed to the 1950s, ride an outdoor "Swamp Train" on a serpentine loop through a tunnel, and explore a train-themed climber, a toddler play area and a S.T.E.A.M. education lab. The museum is largely volunteer-run, with a train club of roughly twenty-five members maintaining the exhibits.

The Gulf Coast layout with its 3D-printed local landmarks and the three LEGO-built layouts are the most photogenic setups. The full-size 1950s passenger car at the entrance and the kid-sized locomotive, gondola, dining car and caboose make good family portraits, and the outdoor Swamp Train and its tunnel offer motion shots. Personal photography is common throughout the museum; confirm any restrictions on tripods or flash with staff, and note that low lighting on some layouts rewards a fast lens or a steady hand.

TrainTastic is unusual among railway attractions in that it is entirely indoor and interactive rather than a heritage line or a static display of full-size equipment. Railfans will find operating layouts across the full gauge spectrum — Z, N, HO, O and G — hand-built by local artisans who are frequently on site and happy to discuss their work. Many exhibits are button-activated, blowing horns, moving bridges and sending sailboats across harbors.

The tribute layouts give the museum genuine regional character: the Gulf Coast display's 3D-printed landmarks and the POW-MIA memorial train are one-of-a-kind, and the LEGO-built layouts (nearly two million bricks) are a draw in their own right. For visitors traveling with children, the ride-on outdoor Swamp Train, the 1950s passenger-car entrance and the play climber make it a full-day stop, and the all-day ticket allows re-entry.

Expect a large, climate-controlled space aimed squarely at families; TrainTastic won the Sun Herald's Best of Coastal Mississippi 2025 award as a family attraction and was a WXXV Viewers' Choice finalist. A typical visit runs two to three hours, but tickets are valid all day, so many families leave for lunch and return. Scavenger-hunt lists keep younger children moving from display to display.

Weekends and school holidays are the busiest times; the museum adds Monday hours in summer (Memorial Day to Labor Day). Seasonal programming is a highlight — the annual Holiday Lights after-hours events in December transform the museum with a lights tunnel, a hot-chocolate bar and Polar Express-themed activities, and a Thomas the Tank Engine exhibit has been announced for 2027.