Plymouth's Mayflower celebrations could be moved to 2021 as the coronavirus pandemic has forced several events to be postponed.
But chief executive Charles Hackett says the Covid-19 crisis means the schedule is now uncertain.
The safety of the public, participants and performers is key and we will respond and follow government and public health advice.
Up to 16 million Americans can trace their ancestry back to the voyage, which set sail from the city in 1620.
The Pilgrim Fathers established one of the earliest colonies and held their first Thanksgiving meal a year later. This is now an annual celebration in the United States.
The following events have been postponed:
24-25 March - Some Call it Home - Theatre Royal – postponed
7 April – Mayflower 400 Sports Quiz – Plymouth Argyle Community Trust – postponed
18 April – Plymouth Albion Takeover Event – Plymouth Argyle Community Trust - postponed
22 April – Sounds of the Ocean City – North Prospect Community Choir - postponed
2 May - Mayflower Football Cup – Plymouth Argyle Community Trust – postponed
3 May – North Prospect Community Choir performance - The Box – postponed
4-10 May – Mayflower Ocean Festival – cancelled, with some elements postponed
8 – 31 May – Plymouth History Festival – postponed
10 May - OSTAR and TWO STAR – postponed
16 May - Mayflower 400: Legend & Legacy – The Box - postponed
16 May – Piazza Walking and Running Event – Plymouth Argyle Community Trust - postponed
17 May – Mayflower 400 Britain’s Ocean City Half Marathon – postponed
23 May - University of Plymouth Choral Society - postponed
23 May – All Nations Ministries Afternoon Tea Dance - postponed
30 May – Mayflower Big Toddle – Plymouth Argyle Community Trust - postponed
31 May 2020 – YMCA Community Fun Run – Plymouth Argyle Community Trust – postponed