Caves management said Transport for NSW had advised that access into Jenolan Caves will be closed to the public for the foreseeable future and, as there is no alternative access to Jenolan, its closure will continue.

"We are unable to provide an exact opening date at this stage, but hope to be back in business mid-May," a spokesperson said.

"The closure extension is required to give Transport for NSW time to finalise their risk assessment of the two-mile road (Oberon side access road into Jenolan), which will provide them with key information needed to determine any traffic management solutions for that road, ensuring the safety of our staff and guests.

"The extension is also required to determine a long-term recovery and access plan for the Hampton Bend and five-mile road (Sydney side access road into Jenolan), which will take considerably longer to repair."

The Jenolan Caves spokesperson said Transport for NSW is undertaking a final risk assessment and recommendations for the two-mile in the next week and "we will have an update once these assessments have taken place".

"This continues to be tough for our business and our staff, and we understand it will be disappointing for a lot of our guests that were hoping to visit," the spokesperson said.

"As outlined previously, we offer complete booking flexibility and our staff are happy to assist you by arranging a voucher valid for up to three years or providing a refund for any cancellations for experiences that have been pre-paid.

"We are in the process of contacting our affected guests, but if you require assistance, please call us on 02 6339 9247 or email bookings@jenolancaves.org.au for accommodation and dining related inquiries.

"Alternatively, you can call 02 6339 9216 or email reception@jenolancaves.org.au for cave tour related inquiries."

Jenolan Caves was closed last month after the heavy rain that came in from the eastern seaboard caused damage to its access roads.