We took a day trip out of Copenhagen today. I purchased a 48-hour Copenhagen Card which includes unlimited admission to several sights and travel on public transportation. We took the train Copenhagen to Helsignor (55 minutes) and then walked to Kronborg Castle, the setting of Hamlet. The castle was 10 minutes by foot from the train station and very easy to find. We then took a 30 minute train to Hillerod and walked 20 minutes to Frederiksborg Castle. The train back to Copenhagen was a quick 45 minutes.