Soft, dark grey sand, with a bit of seaweed on the high tide water mark. The beach is a big bay (15 km long) and is pretty safe as long as you don't ride too far out.
NW wind brings usually fine dry weather with strong winds, and the kind of trees and grass around is a definite proof this is dominant weather. Wetsuit required all year long. Wind is strong, and water not that warm in South NZ.
Main wind is NW, the spot can probably get some good Easterlies as well, but that's just a guess. The bay curves, making several directions sideshore. Futher south E and W, all the way up north N and S.
From the main road Blenheim / Kaikoura (1), next to Seddon, follow signs to Lake Grassmere/Saltworks/Marfells Beach. 8 km gravel road along the lake. Campground at Marfells Beach.
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