Hakone is very close to the ocean. It's basically about 5615 meters from the ocean depending on where you measure to the exact coastline.
If you're driving to a town near the beach or coastline, you could try Odawara.
How far is Avalon from the ocean
How far is Wichita from the ocean
How far is Roanoke from the ocean
How far is Gatlinburg from the ocean
How far is Cleveland from the ocean
How far is Breckenridge from the ocean
How far is Park City from the ocean
How far is Gainesville from the ocean
How far is Pacific Grove from the ocean
How far is Luang Prabang from the ocean