Why did Rama construct bridge to Lanka?
Thanks to @Just_Do_It and @YDS to providing answers and here are two cents from my side:
while watching ramayana (TV series, based on ramcharitmanas and valmiki ramayan). Laxman suggested construction of boats but vibhishan suggested that sinking of boats is easier for lanka warriors (using big stones) so unsinkable medium of travel should be searched. No one knew what to do that's why he suggested to ask solution from ocean.
Note: As my answer is based on TV series, I dont claim it to be 100% correct.
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