long. In New York, US 20 extends 372.32 miles from the Pennsylvania state line at Ripley to the Massachusetts state line in the Berkshire Mountains. US 20 is the longest surface road in New York. It is more historically significant than Route 66.
Why is it more popular that Route 20. Publicity. It was made famous culture by the hit song "Get Your Kicks on Route 66" and the Route 66 television series, which aired on CBS from 1960 to 1964. Route 20 needs someone to write a song about it and/or develop a TV series.
I think it would be wonderful to drive the length of it, exploring all the small towns along the way. That is not going to happen but it is easy to explore Route 20, which is also a Scenic Byway, one area at a time. 
One way to experience Route 20 might be by selecting one county and use it as a base for exploring the area. Schoharie County is a great place to visit. Drive the historic Route 20 Byway between Sharon Springs and Esperance and/or explore Schoharie County’s less-traveled roads enjoying the tranquility and beauty of the countryside taking a few side trips. The county is dotted with classic Main Street towns featuring unique shops with locally made goods, art galleries, restaurants, and restored turn of the century accommodations. Step back to an earlier time in Carlisle, Cobleskill, Esperance, Middleburgh, Sharon Springs, and the historic village of Schoharie. In Sharon Springs don’t miss the Beekman 1802 Mercantile made famous in the “Fabulous Beekman Boys” of reality TV fame. Too bad they didn’t use the show to promote Route 20 and write a hit song “The Fabulous Beekman Boys of Route 20!”
Schoharie County is dubbed the “County of Caves.” For six million years Mother Nature carved out amazing underground caverns. The most famous is Howe Caverns where visitors descent 156 feet below the Earth’s surface to journey through the expansive main cavern marveling at the stalactites and stalagmites and then take a boat ride on the underground River Styx. If you haven’t been to Howe Caverns in a while then you will be amazed at all the adventurous things to do besides explore the cave. There is a zip line, ropes course, rock wall, H2OGO Balls, a motel, and more. Nearby is another underground wonder, the Secret Caverns, complete with a waterfall. 
Before the first European settlers arrived in 1712 the area was home to the Iroquois. The Iroquois Museum, near Howe Caverns, is housed in a building that recalls the traditional longhouse offering an insight into Iroquois culture by promoting Iroquois art and artists. There is a nature trail plus a variety of festivals, events, and learning activities for all age groups.
The Old Stone Fort Museum Complex in Schoharie includes several buildings: a 1700s home, a 1780 Dutch barn, a one-room school house, plus a 1772 stone church that was fortified and attacked by the British forces in 1780. Take note of parishioners’ names that the builders chiseled into the stones. The Treasure Hunt of the Fort’s eclectic museum collection is fun for all ages. Try to find a shield from the Philippines, a button with a photograph on it, and a glass tombstone. A variety of historical events are reenacted throughout the year.