A fantastic relic in a rotten city. Rich with history, off the beaten path and perfect for photos, the welcome sign is one of the most iconic signs in the world. It's a must do for most tourists.
Two tips:
1) Visit in the morning, preferably before 10am when the tour buses arrive. Another option is to visit at night when most people have gone to bed or on to other things.
2) Watch out for the creepers in normal clothes who offer to take your picture. They appear normal at first, but then things get weird and they expect money following the photo opp. Avoid them and get other tourists to take your picture.