What is the largest UFO museum in the US?

I am a huge UFO fan and the largest museum is probably the The International UFO Museum and Research Center Roswell, NM. Here is some info: 114 North Main

Roswell

NM 88201

USA Phone: 505-625-9495

Fax: 505-625-1907 Postal Address: IUFOMRC

P.O.Box 2221

Roswell

NM 88202

USA