Because of the crowds expected in Washington for Saturday’s March for Our Lives anti-gun-violence rally, officials have moved the opening ceremony for the National Cherry Blossom Festival to Sunday.

“Based on reported crowd estimates, road closures, and recommendations provided by city officials and agencies, this decision has been made in careful consideration of our ticketholders and performers,” the festival’s organizers said in an announcement Monday.

The event was originally scheduled to be held Saturday at the Warner Theater, just a short walk from where as many as 500,000 people are expected to be rallying as part of the March for our Lives organized by survivors of the mass shooting at a high school in Parkland, Fla.

The march itself is expected to create challenges for the region’s transportation system.  Combined with the Cherry Blossom Festival activities, Saturday was expected to be one of the busiest days this year to be traveling to downtown and monumental Washington.

By moving the Cherry Blossom Festival opening ceremony to Sunday, officials say, they will ease some of the extra burden on Metro and ensure visitors have “efficient and convenient access” to the ceremony Sunday. The opening ceremony kicks off the four-week festival and marks the official beginning of tourism season. Other festival events are scheduled to be held throughout the week and thousands of visitors are expected to be in town to view the blooming cherry trees at the Tidal Basin.

Metro will be running rush-hour service Saturday, but officials say stations and trains will likely be crowded. Even with the Cherry Blossom Festival ceremony moved to Sunday, visitors should plan their trips in advance and anticipate large crowds on their travels.