ORGANISERS of the Challenge Henley ultra-triathlon have provided emergency helplines for residents along the cycle route, along with a full list of roads likely to be affected by the closures.
The event, on Sunday (18), will see athletes complete a 3.8km swim, a 180k cycle and a 42km run in Henley and the surrounding area.
Road closures and one-way traffic are planned along the cycle route, effectively closing off several properties.
Residents along the route will be able to call race organisers on the emergency number and motorcycle marshals will be dispatched. They will then escort residents to and from their homes.
A race spokesman said: "We would ask for your patience and if you do have a necessary journey please allow extra time. If you could give us advance warning on the day that would be even better."
The numbers, which can only be used on race day, is 01494 570536 or 07584 087305.
Roads that are going to be closed with approximate times are:
* A4130 between the A4155 and B481 Nettlebed - 6am for up to 12 hours.
* Unclassified road between the A4130 and Rectory Lane, Nettlebed - 6am for up to 12 hours.
* B481 between the A4130 to Greys Road, Rotherfield Peppard - 6.30pm for 11 hours.
* B480 between the A4130 and B481 - 6.30am for 11 hours.
* Unclassified road passing through Greenfield/Christmas Common between the B4780 and Bucks county boundary - 6.30am for 11 hours.
* A4130 New Street between Bell Street and Thameside - 11am for 13 hours.
* A4130 Thameside from New Street to Hart Street - 11am to 13 hours.
* Finlay Drive, Henley for its entire length - 10.30am for 13 hours.
* Phyllis Court Drive, Henley for its entire length - 10.30am for 13hours.
* Radnor Close, Henley for its entire length - 10.30am for 13 hours.
* Marlow Road from Henley Business School to Henley - 6am to 10am. (Will be open northbound while competitors cycle southward.)