Uluan Peninsula is a peninsula jutting out into Lake Toba on the eastern side towards Medan, in Simalungun Regency and Toba Samosir Regency of North Sumatra province. It has experienced a large amount of uplift since the series of massive volcanic eruption that began 1.2 million years ago, the most recent 70,000 years ago and among the largest known eruptions on the planet. Uluan is located on the Porsea caldera, a part that erupted ca. 800,000 years ago. Parapat, the primary transit point for tourists going to the lake, is located on Uluan.