Too many days in the Rockies apparently got to Lady Gaga.
The pop star/performance artist brought her "artRAVE: The artPOP Ball" tour through the Mountain time zone this week — Monday night here in Salt Lake City, and Wednesday night in Denver.
After the Denver show, though, Lady G. was briefly hospitalized for altitude sickness, according to Celebuzz. She even posted, via Instagram, a photo of herself in an oxygen mask — which, style maverick that she is, she was wearing upside-down.
Gaga is back at sea level this weekend, performing in Seattle tonight and Vancouver on Saturday. Then the tour goes international, next week in Japan and Korea, finishing out August in Australia before spending the fall hitting stops in the Middle East and Europe.