algae beach cliff coastline Cornish cornwall England english Great Britain holiday leisure natural nature ocean resort rock sand sandy sea seaweed shore surf tide vacation water waves adventure boat canoe canoeist float fun hobby kayak outdoor paddle Pembrokeshire sport ten travel united kingdom wales welsh blue cove pleasure rocky yellow current fierce flow foam green norway norwegian outflow pour pure raging river rocks spray steps summer tiers torrent torrential trees Tvindefosse violent waterfall arid barren brown bushes clouds desert dry harsh hills Israel Judea Judean landscape limestone mount mountains rainstorm sere severe sky stark storm track trail vegetation gorge ravine route wadi