And the Road Trip Picture of the Day winner is...

He said he was "going for the gold," and he wasn't kidding.

On May 30, as part of Road Trip 2011, I launched the Picture of the Day challenge, and for the next 70 days, I posted a new daily photograph from my travels. Your job was to correctly identify it.

Based on the fantastic response to last year's challenges, I knew that the competition for this year's grand prize--a major brand video game console--would be fierce. And I was right.

Out of that total of 70 possible correct answers, the grand prize winner--Phil Yao of Cambridge, Mass., who wrote in his submission on that first day at the end of May that he was "going for the gold"--got 67 right, a very impressive performance.

Of course, Yao wasn't alone. Other top performers got 66, 65, and 63 right answers, respectively. But I can only award one grand prize, and Yao won it. How did he do it? In a message explaining his methods, Yao demonstrated that it was a combination of great search skills, a partnership with some helpful friends, and a refusal to give up until he'd come up with each day's answer.

"The Road Trip Picture of the Day challenge has been such a crazy, frustrating, and awesome addition to my summer," Yao wrote me. "I never really entered into it for the prize, but rather for the intellectual challenge it presented and for the momentary excursion into some random window of the world it gave...

"The most important resource, as old-fashioned as it may sound, is other people. The great thing about this contest is that collaboration is allowed, and without the help of other people, I definitely would not have been as successful as I was this summer. Often, the conversation and give-and-take of opinions was crucial to locating the country in which the object was and ultimately the object itself. I think that a human mind is capable of filtering and sorting through information in such complex ways, and when you solicit the help of others, you get a bunch of vastly different approaches to the information present in the picture. Though I was able to do most of the challenges on my own, the trickiest challenges were helpfully deconstructed by the numerous perspectives I was lucky to have."

Yao continued, pointing out that it wouldn't have been possible for him to win without a strong background in architecture, art, and other areas that helped him identify elements in the daily pictures. "It helps to be able to recognize what a flying buttress, a rose window, a concert hall, or a cable-stayed bridge typically looks like," he explained. "I've always been fascinated by art and architecture, and I think I absorbed a lot of the descriptive language for these works through reading random journals and perusing Wikipedia when I was bored. Having a store of general knowledge accessible was definitely helpful."

And then there was the technology. "Google released a new tool which allows one to drag and drop a picture (or its URL) into the search bar--afterwards all images with a similar composition pop up. Often I had to put in a keyword in conjunction with the image to find an image matching the picture of the day, an added layer of filtering which would focus the results," he wrote. "Many times, the country of location was the crucial key to filtering for the relevant images. Patience was also important, as the relevant image would sometimes be on the thirtieth page or so. Google's tool seemed much more effective in most instances than other similar tools did. On four or five occasions, Google's tool would even suggest the correct subject of the picture. I remember that the Chateau de Castelnaud was one of those locations which automatically popped up after inputting the picture. However, whenever the lighting or angle was atypical, the tool would often hit a dead end.

"When this was the case, I and my friends had to do some stranger forms of hunting. For example, in the case of the Eagle of Geneva, which eventually only eight people got right, we initially hit a rut. After unsuccessful searches, we ended up looking at the Picture of the Day and trying to take in the feel of the pictured canal and its banks. We then strolled down the canals of many cities in Europe--on Google Maps. We saw that Amsterdam and Copenhagen were out of the question in terms of different atmospheres. My friend Jake was 'walking' through Geneva when he realized that the atmosphere felt right, and he soon came upon the Eagle of Geneva on the side of the street near the Pont de la Coulouvreniere. This was an atypical find--usually Flickr worked best as an alternative resource because people naturally upload pictures of interesting things they see and many of them take the time to add on descriptive tags.

"When one part of the picture proved fruitless, I would often shift the focus to another part of the picture. For the ancient cave dwellings in La Roche Blanche, despite numerous on-target searches for ancient cave dwellings on Flickr, I was really at a loss to find any pictures remotely resembling the black holes dotting the cliff. I switched my focus to the red-tiled roofs of the town and the shape of the chapel steeple occupying the bottom edge of the picture. I then reasoned that if these were truly ancient cave dwellings, tourists would probably have been able to access them and would have stood inside them to take sweeping pictures of the town below. In fact, after some searches in which I was specifically keeping my eye out for that kind of shot, I was able to find a picture from a reversed perspective, with the mouth of the cave framing the view of the sunny town below. It was an eleventh-hour revelation, and it really felt awesome to see that town sitting happily on the plain down below. I would not have noticed the picture with the reversed perspective unless I had consciously been looking for it. In other words, before I had been looking for holes when really, I should have been looking for windows."

This is heady stuff, and some will say Yao may have a bit too much time on his hands. But for me, it was very interesting to see how Yao and others arrived at the answer day in and day out, regardless of whatever else was going on in their lives, and almost always in spite of how hard the picture was to identify. I wanted people to be able to get the answer, without it being too easy (usually). So, to throw people off the trail, I posted photos out of geographical order, and took screenshots of the downloaded photos in order to strip out the metadata. But still, day in and day out, Yao and his closest competitors were there with the right answers. And many others were, too. All told, I received 6,935 correct answers, as well as 850 incorrect responses. That means that people who responded were right 89.1 percent of the time, suggesting that most people wouldn't write in unless they were pretty sure of the answer

So, to those top performers and everyone else who took the time to play this summer, my heartfelt thanks. Please come back next summer for the Road Trip 2012 Picture of the Day challenge.