It is actually a pretty relaxing and cheap way to spend the afternoon. Admission is something like 1,000 won. Add 1,000 won for a program and maybe 2,000 for snacks and you are still well under the price of a movie ticket. That leaves you with plenty of money to blow betting on the races. OK, I didn’t lose that much since I never bet more than 1,000 won on a race. In fact, my net loss was only 1,400 won for the day. There are few things you can do in Seoul for that kind of money.
So, if you have an afternoon to kill with a friend, I can think of worse things you can do.
One thing I would recommend is that you pick up some gimbap or other snack before you get on the subway for the trip. The snack selection there is pretty weak and I didn’t notice any food vendors on my way in.
Here are a couple of pictures to give you a feel for the place: