We spent 2 hours on the self guided tour but we read everything we could. There is a cost of about $9 to take the tour and it help with the upkeep. There is also a little chapel with either a mass or prayer service at 12:15pm during the week. So much history.
It depends on where you are! We were on the beach and walked easily almost an hour.
To tour the inside of Carmel Mission very quick 30 Minutes. One hour is good. If you are religious or history student 2 hours.
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