Seoul Lantern Festival

The Seoul Lantern Festival is an annual event held at Cheonggyecheon Stream.The festival is a  remarkable display of hundreds of lanterns (one site mentioned 30,000 lanterns in all). The various entrances to the stream are blocked so that visitors must enter at the beginning (then everyone is headed the same direction for the most part).  We ended up at the other end, walking backwards (not knowing there was a directional flow), but we weren't the only ones.

The line snaking around the stream entrance.

The festival lasts for 3 weekends.  We managed to visit on the first night of the festival, figuring there would never be a "good time" to see it.  Since the festival was right downtown we decided it would always be busy.  It turned out to be a great, busy activity.
The lanterns aren't your typical Chinese lanterns.  They are huge displays/creations that are lit.  They don't float on the stream (although you can pay to make a paper lantern to float on the stream).  They are mounted on huge platforms and lit with electric lights.  It is still a pretty sight.