The South Island's biggest cycling event is set to attract more than 4000 visitors to Marlborough over coming days.
Cyclists from around New Zealand, Australia, Europe and Asia, and their families and supporters, will start arriving in Marlborough tomorrow in preparation for the annual Forrest GrapeRide.
Race director Pete Halligan said 2500 riders would take part in five events running until Saturday.
Business has been brisk at hotels, motels and B&Bs in Blenheim and Picton.
At motels in Blenheim, only six studios, one one-bedroom and one two-bedroom unit were available yesterday afternoon.
Marlborough Motel Association chairman Noel Noble said most visitors were domestic travellers from New Zealand and Australia.
Visitors had booked out the rooms immediately after last year's GrapeRide, Noble said.
"It is anticipated rooms will be a sellout by the weekend."
Halligan predicted it would be the biggest retail weekend of the year, with a strong domestic and international contingent taking part in the races.
Around 130 Marlborough riders had entered. In terms of domestic visitors, 42 per cent came from Christchurch, 18 per cent from Wellington, 10 per cent from Auckland, and 5 per cent from Nelson.
The 200 riders from overseas included a 35-strong group from Japan, plus others from Australia, Europe and the United Kingdom.
The races were a major economic boost for Marlborough.
"The demographic of visitors who come means they tend to spend quite at lot. The domestic and oversees tourism opportunity is massive for Marlborough.
"People tell me they want any excuse to come to Marlborough. Events like the GrapeRide and the Saint Clair Vineyard half marathon really enhance our wine-industry tourism."
It is second only in numbers to the Contact Lake Taupo Cycle Challenge and organisers in Taupo had approached GrapeRide to work in tandem, Halligan said.
For the first time, a recreational cycle will follow the route tomorrow. The three-stage gourmet graze taking in Picton, Havelock and Renwick starts at the Forrest Estate stonewall at 9am.
The 101-kilometre ride has been marketed to leisure riders who want to take in the region's stunning scenery, food and wine.
Watch out for GrapeRiders on our roads
GrapeRiding for Ella and CanTeen