As festivalgoers started arriving at the site, some reported having been stuck in traffic overnight
The Glastonbury festival in the UK is said to be 'fully open for business' after major delays earlier in the day.
Some people had been stuck in queues around the site throughout the night, with one calling the organisation "shambolic".
A statement posted on the festival's Twitter feed on Wednesday morning said: "If you are coming to the festival by car or campervan, and have yet to begin your journey, please do not set off."
It said wet weather and ground conditions was causing "heavy traffic congestion" around the festival site in Somerset.
The statement urged anyone who has already set off to "stop somewhere safe and warm".
One person responded: "Bad planning and management are causing heavy traffic congestion - not rain!"
Another said: "This post should have been put up hours ago."
One said: "Journey is now into 24 hours, worst festival experience after 15 years. Shambolic."
The statement added: "If you are already on the site, gates will open as planned. But, as always, there is no entertainment today. The festival's entertainment does not begin until Friday."
An updated statement at lunchtime announced the festival was 'fully open for business' following the earlier delays.
Organisers said 'everyone is welcome to travel' to the Somerset site, although advised people they can still expect to queue:
People who gained access to the site this morning encountered very wet and muddy scenes, although there was sunnier weather during the afternoon.
This year's festival is being headlined by Coldplay, Adele and Muse. The festival sold out in a record time of around 30 minutes when tickets were released last October.