Sentence:  Now we plunged into a deep shade with the boughs lacing each other overhead, and crossed dainty, rustic <WSD>bridges</WSD> over the cold trout-streams, the boards giving back the clatter of our horses' feet: or anon we shot into a clearing, with a colored glimpse of the lake and its curving shore far below us. 
Meaning of the word marked with <WSD> tags:  A construction spanning a waterway, ravine, or valley from an elevated height, allowing for the passage of vehicles, pedestrians, trains, etc.