From Illinois, take Route 36 across the "new" Hannibal bridge. Take the first Missouri exit, which is "Route 79, Hannibal Downtown". At the bottom of the ramp, turn left, and go back to the East on "old" Route 36, Mark Twain Avenue. From Missouri, take Highway 61 into Hannibal, and turn left and go east on Route 36. Take the "Route 79, Downtown Hannibal" exit. At the bottom of the ramp, turn right on "old" Route 36, Mark Twain Avenue.
Going east on "old" Route 36, when you get close to where Highway 79 turns south, get in the left turn lane before you get to the orange construction cones, and turn left into the driveway just past Mailboxes and Parcel Depot. Go up a steep, narrow road which leads you to the Mark Twain Memorial Lighthouse on Cardiff Hill, which overlooks the Mississippi River. There is a parking lot and steps leading up to the lighthouse. Or you can drive on around to the north and come in the driveway to the lighthouse from the north side - the gate will be open.
Alternative route -- From old Rt. 36, turn left on Reservoir Street, just past the Hannibal Travelodge motel, and just before the 5th St. overpass across Rt. 36. Go to the top of the hill, and then turn right on Cardiff Lane. Follow Cardiff Lane around to the South to the driveway with the open gate and come on in. You'll see our operating site just 50-100 yards inside the gate.
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