For easy views with little walking, drive Trail Ridge Road and stop at the overlooks. The road usually closes mid-October, so check the road status before you go. For a hike, start at Bear Lake, or continue on to Dream and Emerald Lakes for something more moderate. Alberta Falls is another good short hike. October is elk rutting season, so keep an eye out in the park and around town. Note: RMNP requires timed-entry reservations during peak season, which may be required in early October.
Take the historic red tram to the summit of Prospect Mountain for wide views of Rocky Mountain National Park and the Continental Divide. There are short trails and a café at the top. The tram typically runs through early November, so check the schedule before you go.