It may not be until early June. They are building a new visitors center this winter.
According to the PUBLISHED INFO collected by GOOGLE Technologies - Timpanogos Cave National Monument will be open 7AM to 7pm DAILY ... due to weather conditions ALL IN QUESTION should call and ASK a PARK RANGER... or checkout their DOMAIN at the National Parks PLATFORM @nps.gov https://www.nps.gov/tica/index.htm
Usually May through September. Last year it opened on May 19
Pretty sure after memorial day
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