Promotional value expires 120 days after purchase. Amount paid never expires. Subject to availability. Reservation required, 48 hour advance notice required. 48 hour cancellation notice required or fee up to voucher price may apply. Sales tax not included. Valid every day of the week; Tue. and Fri. only at 2 PM, Sun, Mon, Wed, Thur, Sat at 10AM and 1PM. Not valid for church, school, boy/girl scout, or other groups larger than 4. Not valid on US holidays. Must arrive 45 minutes prior to scheduled tour time. Must sign waiver. Subject to weather. Credit card required at booking. Limit 1 per person, may buy 4 additional as gift(s). May be repurchased every 180 days. Limit 1 per visit. Merchant is solely responsible to purchasers for the care and quality of the advertised goods and services.