Experience New England's highest peak on the world's first mountain-climbing cog railway! Since 1869, this National Historic Engineering Landmark has been the vacation highlight of visitors from around the world. The three-hr round trip NOW includes approximately one hour at the summit and free admission to the Observatory Museum. NEW on-board Audio Tour. Choose biodiesel or steam trains. Base Station, Museum, Restaurant. Open April to November. Advance ticket purchase recommended. Visit thecog.com for schedule details, discounts and special events.