We arrived at the site in the mid-afternoon after a visit to Pompeii. The town is much smaller than Pompeii but there were probably less than 50 people there. The houses and the streets are not as grand as those in Pompeii but we could go inside some of the larger homes and the baths and be alone. As a result, the ruins seemed more understandable and intimate. I don't think I would substitute Herculaneum for Pompeii but it is a very nice supplement if you have the time and interest. We visited the same day as Pompeii and they did not charge it as a separate admission on our three day card. The site is not well marked from the train station but is easy to find: leave the station going downhill and continue in an almost straight line until the road comes to a T at the entrance to a park -- the ruins are thourgh the gate.
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