A solo traveller enjoying Dublin's old town. Credit: Oleh_Slobodeniuk/Getty Images The Irish city of Dublin has long been an easy city to explore solo, thanks to its compact city center, friendly pub culture, and deep literary roots. Now, it has the title to match: the Irish capital was just named the No. 1 solo travel destination in the world by Tripadvisor. The booking site's annual Travelers’ Choice Awards "Best of the Best" list highlights destinations that earned an exceptional number of glowing traveler reviews over the past year. Fewer than 1 percent of Tripadvisor’s more than 8 million listings worldwide receive the distinction, which is calculated over a 12 month period, placing Dublin at the top of a highly competitive global field. For its part, many of Dublin’s marquee attractions are within easy walking distance of one another, making it a breeze to fill a day without overplanning. Tour Trinity College and view the Book of Kells, stroll through the historic St.…