Prince Harry and Meghan Markle’s wedding will be a jam-packed day of tradition, ceremony and celebration. Here is a detailed break-down of how the day will unfold, according to Kensington Palace and the official wedding program.

4 a.m. ET
9 a.m. British time

Members of the public who are invited inside the grounds of Windsor Castle arrive. Among the guests are 1,200 volunteers invited for their charitable work.

4:30 a.m. – 6 a.m. ET
9:30 – 11 a.m. British time

Wedding guests arrive at Windsor Castle’s Round Tower by coach. These guests will then proceed to the south door of St. George’s Chapel, where the ceremony will take place.

6:20 a.m. ET
11:20 a.m. British time

Prince Harry and The Duke of Cambridge, Prince William, arrive at St. George’s Chapel. They will most likely arrive by foot, according to Kensington Palace.

Around the same time, Meghan Markle and her mother, Doria Ragland, begin their journey to Windsor Castle. The journey will pass members of the public.

6:25 a.m. ET
11:25 a.m. British time

Members of the Royal Family arrive at the chapel’s Galiliee Porch.

6:40 a.m. ET
11:40 a.m. British time

Prince Harry and Prince William arrive at the west door of the chapel.

Round tower Windsor Castle

6:42 a.m. ET
11:42 a.m. British time

The Prince of Wales, Prince Charles, and his wife Camilla, Duchess of Cornwall, arrive at the Galilee Porch.

6:45 a.m. ET
11:45 a.m. British time

Meghan Markle’s mother, Doria Ragland, arrives at the Galilee Porch.

6:52 a.m. ET
11:52 a.m. British time

By this point, there are only two people left to enter the chapel: the Queen and Meghan Markle. Like the rest of the Royal Family, the Queen will enter at the Galilee Porch.

Before Markle enters the chapel through the west steps, she will meet with some of her bridesmaids and page boys. Among those page boys will be 7-year-old Brian and John Mulroney, the sons of Jessica and Ben Mulroney.

A fanfare will then sound, signaling the entrance of the bride.

St George's Chapel.

7 a.m. – 8 a.m. ET
12 p.m. – 1 p.m. British time

The wedding ceremony begins. The service includes both British and American clergy. Archbishop of Canterbury Justin Welby will officiate the wedding, and Dean of Windsor bishop David Conner will lead the service. Michael Bruce Curry, the American presiding bishop of the Episcopal Church, will deliver the address.

Near the beginning of the ceremony, the archbishop will ask “anyone present who knows a reason why these persons may not lawfully marry” to declare it. He will then ask Harry and Meghan if they will love, comfort, honour, protect and be faithful to each other as long as they live.

Each will reply “I will.”

A choir will perform songs throughout the service, including “Stand By Me,” the 1961 song by American singer-songwriter Ben E. King.

At the end of the ceremony, the newlyweds will leave the chapel to the tune of “This Little Light of Mine.”

8 a.m. – 8:30 a.m. ET
1 p.m. – 1:30 p.m. British time

Following the ceremony, Prince Harry and Meghan Markle will leave the church. The first thing the married couple will do is acknowledge the 200 representatives from Harry’s charities. They will then make their way to their horse-drawn carriage, where they will embark on a 15- to 25-minute ride through the streets of Windsor.

The remainder of the day:

Kensington Palace has not released a detailed timeline for the rest of the day. An evening wedding reception will be held at Frogmore House, a royal residence near Windsor Castle built in the late 1600s. An exclusive list of 200 guests are invited to the reception, hosted by Prince Charles. Elton John and model Cara Delevingne are expected to attend the party.