Trampers will have to wait until June before they can book on one of the country's iconic Great Walks due to technical issues.

Last Thursday, the bookings website crashed for several hours after 10,000 people tried to book on the Milford Track just after opening.

It was effectively sold out within hours despite the system crashing.

Bookings for the Kepler Track, Abel Tasman Coast Track, Rakiura Track, and Whanganui Journey were meant to open at 9.30am this morning.

Before bookings opened, the Department of Conservation told RNZ it was not expecting another Great Walk booking system crash, saying their server capacity remained scaled up.

However, multiple attempts to reserve a spot failed until the website was directed to a new page detailing the delay.

The Department of Conservation has since confirmed bookings planned for today and tomorrow will be delayed until June.

This will also impact the Paparoa Track, Routeburn Track and Tongariro Northern Circuit

The dates for these new release dates have yet to be confirmed.

In a new statement, DOC booking services manager Cameron Hyland said the new dates would be posted on its website and via social media later this week.

"Due to ongoing technical issues being worked on by our IT vendor, we have chosen to postpone the bookings opening dates rather than put people through the stress of dealing with delays and errors."

In an earlier statement, Hyland said a systems crash was definitely not a good look, but the underlying cause has been addressed.

"We had a smooth opening for the Milford Track last year, and we took all the same steps as well as some new ones to make sure we were as prepared as possible - so we're extremely disappointed to have experienced this new issue.

"We'll be having tough conversations with our vendor about what we can do over the coming months to ensure that, when we open next time, they are confident we're not going to have this happen again."

Main image (Photo: 123rf.com): Kepler Track.