In spring 2019, the Walt Disney Company announced that effective May 1, 2019, there would be size limitations on strollers that could enter the parks and that stroller wagons were being added to the list of items with wheels (i.e. skateboards, scooters, inline skates, shoes with built-in wheels, pull wagons, and wheeled mobility devices with less than 3 wheels, among others) that could no longer be brought into the park. It was said to have been done in an effort to alleviate stroller congestion and improve park traffic flow.
From WDW’s website (Disneyland has a similar page on their website):
Why are you reducing the size of strollers and prohibiting wagons in your theme parks and water parks?
Walt Disney World Resort makes updates from time to time, and the reduction of stroller sizes is intended to ease guest flow and reduce congestion, making the park experience more enjoyable for everyone who visits. Many strollers, including many double jogging strollers, fit within these guidelines.
Are stroller-wagons permitted?
Stroller wagons, whether pushed or pulled, will not be permitted at any theme park or water park or at indoor venues at ESPN Wide World of Sports Complex.
What if my stroller is larger than the size allowed?
Strollers are available for rent at the parks. Guests who have additional questions on the stroller policy may visit Guest Relations for more information.
How do I ensure my stroller falls within the size guidelines?
Strollers should be no larger than 31” (79 cm) wide and 52” (132cm) long when measured across the widest and longest points.
To ensure that their guests understand the new rules, Disneyland and Walt Disney World both placed size check locations outside each of their respective parks…
— WDW News Today (@WDWNT) May 1, 2019
…but that doesn’t do you a whole lot of good if you bring your stroller from home and it turns out to not fit. So lots of future Disney guests are (hopefully) measuring their strollers before they take them to Disney.
OR they can use our lists…;-)