Algernon Blackwood 
The Willows 

After leaving Vienna, and long before you come to Budapest, the Danube enters a region of singular loneliness and desolation, where its waters spread away on all sides regardless of a main channel, and the country becomes a swamp for miles upon miles, covered by a vast sea of low willow-bushes. On the big maps this deserted area is painted in a fluffy blue, growing fainter in color as it leaves the banks, and across it may be seen in large straggling letters the word Sumpfe, meaning marshes.