In the interior of the West Antarctic Ice Sheet (WAIS), mountains that project through the ice sheet serve as dipsticks that gauge past ice sheet elevations.  Thickening of the WAIS is recorded by moraines, erratics, and trimlines on mountain slopes.  In the Ohio Range, near the WAIS divide, such features indicate that the last highstand was ~ 120 m higher than present. The youngest exposure ages of erratics near the trimline indicate that the last highstand occurred ~12.5 ka.  However, most erratics have older exposure ages. Prominent clusters of exposure ages occur around 30 and 70 ka, periods corresponding to the onset of glacial stages in the d¹⁸O record.  ²¹Ne exposure ages of cavernously weathered bedrock below the trimline indicate  > 3.5 Ma of cumulative exposure.  In contrast, nominal ¹⁰Be exposure ages of the same samples are ~1.1 Ma indicating that the bedrock was ice-covered for a minimum of 1Ma.