Odaiba Marine Park, 1-4 Daiba, Minato; Don’t let the name fool you: this is most certainly an artificial beach, so much so that swimming is not allowed (though the occasional toe dip is gotten away with). No matter. When the sand’s good enough to build a castle or two, who’s complaining? staying to watch the sunset over the city. It’s a great vantage point and a frequent spot for couples on date nights.