Saluton kaj bonvenon al Esperantujo!

Anywhere where you can find a Pasporta Servo host, essentially an Esperanto-speaking couchsurfing host. I have heard many good things about Brazil, Iran, France, Sweden, Germany...

A good place to travel is Berlin, which has seven Esperanto clubs. There's always something happening in Esperanto Berlin.

I don't know of any places that have such a high amount of Esperanto speakers that you can ask a random person in the street something in Esperanto, unless there is an Esperanto event happening there.

Travel to an Esperanto event, make some friends and you can travel all over the world to meet them again.