Many of Tokyo's finest restaurants are so hidden away you hardly know they're even there. But there's little chance of missing Maruka. In the unlikely event that you fail to spot the large white noren curtain across the entrance, you won't miss the long line leading up to it.

Year-round, rain or shine, you can expect to wait outside that doorway — often for 45 minutes or more. What's the deal? And is it worth it, just for a meal that will take a quarter of that time to finish? The answer depends on how much you like udon noodles.

Maruka serves the chunky white wheat noodles that are a specialty of Kagawa Prefecture, better known by the area's feudal name: Sanuki udon. Many aficionados say nowhere in the city does them better, and it's hard to disagree with that assessment.