On February 12, 2014, a sinkhole opened under the floor of the Skydome area of the museum at around 5:44 AM local time, causing a portion of the floor to collapse. Kentucky is one of the many states that is popular for having karst topography. Karst topography is the landscape that is formed from the dissolving of rocks such as limestone. In the museum's case, the sinkhole was caused by the dissolving of the limestone in the ground which caused pockets to open underneath the surface. Eventaully, the weight of the building caused the top layer of soil to collapse. Eight rare and one-of-a-kind Corvettes, portions of the display stands and rails, large concrete floor slabs and dirt fell into the sinkhole, causing serious damage to some of the Corvettes. The Corvettes involved have an estimated value of a million dollars.〔http://www.bgdailynews.com/news/local-contractor-will-help-remove-reported-million-in-corvettes-from/article_773f14c0-d55e-5925-9361-29635b40349f.html?mode=jqm〕 The remaining 20 cars in the Skydome were immediately removed from that area. Starting March 3, 2014 through March 6, 2014, 5 of the 8 Corvettes were recovered from the sinkhole. The spire area of the Skydome is being reinforced before work starts on removing the final three buried cars. Multiple multigravity tests were done to insure that another sinkhole wasn't present or in the making. The results came back clear which allowed for the construction work to begin. For added precaution, micropiles, or systems of steel rods, were insterted into the ground before the concrete was repoured to help give the building more support.〔Katie Frassinelli〕 The museum reopened the day after the sinkhole appeared.