A word of advice!
Unless you are strongly considering JHU, I recommend not taking the interview. The travel agency was a huge hassle, the weekend was largely unorganized, and it has been 4 months and I have not been reimbursed and the person responsible for reimbursements will not respond to emails/phone calls. If you are genuinely interested in the program, of course go check it out but I was on the fence and regret going especially now that I am still waiting on 500$ of reimbursements and it doesn't seem to be coming my way anytime soon.