I'm very satisfied with Book2Park's service - Good price, no hidden fees, easy booking online, provided clear instructions & friendly reminders. I'll use again. Recommended! Doubletree by Hilton hotel parking lot is only a few minutes away from BWI Airport. The staff at the front desk is nice and professional. Free shuttle that runs every 30 minutes is reliable (We took the shuttle at 4:30am). And the shuttle driver was very friendly and helpful. I'd choose this place again. Recommended! Thanks.