1) Boardwalk 2) Planking for marshy ground 
Platform of wooden slats built over muddy ground to form a dry path. During World War I, army engineers used duckboards to line the bottom of trenches on the Western Front, as these were regularly...
Where a roof has lead or copper gutters or platforms, slatted wooden walkways - duckboards - should be fitted, to prevent damage to the metal covering during routine maintenance and inspection. Duckboards also allow water to drain away after heavy snow. Related Words: Copper; Gutter ; Lead
[n] - a boardwalk laid across muddy ground
noun a boardwalk laid across muddy ground
a board or boards laid as a track or floor over wet or muddy ground.