Trevor Thomas and his guide dog and thru-hiking companion Tennille have returned to Colorado to finish a segment of The Colorado Trail that they were unable to complete last summer. Thomas, who is blind, hiked The Colorado Trail from Denver to Durango last year, but snow from a June storm shut out the route through the high terrain of the Collegiate West section of the trail for Thomas and his Labrador retriever. Thomas, Tennille and former Denver Post photo editor Dean Krakel, who is documenting the journey, will set out from Twin Lakes on Sunday to hike the 160-mile Collegiate Loop, which combines the Collegiate West and East — the slightly lower-altitude option for hikers through the central mountains. Krakel has noted that other hikers often don’t realize they’re talking to Zero/Zero — Thomas’ trail name, which denotes what the 46-year-old from Charlotte, N.C., would register on an eye chart.