alone bare bleak countryside crataegus distorted England field grass Great Britain green hawthorn hill isolated landscape pair rural South Downs summer Sussex tree two view windswept bank clouds erosion Gower meander natural nature Oxbow Pennard Pill river sandy sky Three Cliffs Bay trees valley wales water welsh woodland blue cloud dwindle edge high icy July margin melt mountains norway norwegian plants plateau pool retreat road rock snow thick white cold cover deep far freezing remote ridge snowy Thaw wild concrete english evening fields geodetic hills landmark location marker meadows pillar point station survey triangulation trig viewpoint altitude austere boulders habitat harsh melting resilient rocks rough rugged route transport