Paris-Roubaix is known as "the hell of the north" because of the bone-jarring cobblestone roads the peloton races over.

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The ancient roads test the strength and fortitude of classics stars and their equipment.

The rough, uneven surface is miserable to ride across and the narrow corners are treacherous. When it is hot, the stones become coated in a slick layer of dust, and when it is wet, all hell breaks loose.

Gregor Brown highlights the three most crushing sectors of the race; Mons En Pévèle, Pavé de Luchin (Carrefour de l'Arbre) and of course Trouée d'Arenberg (Arenberg Forest).