The conical island of Nevis, lying across a narrow channel from St. Kitts (St. Christopher) Island, is a composite cone with overlapping summit craters.  An unnamed lava dome is located NE of the rims of the two craters.  Nevis Peak, the 985 m high point of the island, is located on the outer crater rim.  The inner crater truncates the western rim of the earlier crater and is widely breached on the west side.  A small lava dome was emplaced within the inner crater in recent pre-Columbian time, and pyroclastic flows and mudflows were deposited on the lower slopes of the cone.  Four lava domes were constructed on the flanks of the volcano.  Madden's Mount and Butlers Mountain were built on the NE and eastern flanks, respectively; Mount Lily lies on the NW coast and Saddle mountain on the southern coast.  No historical eruptions are known from Nevis, and the youngest dated eruption was about 100,000 years ago.  Active fumaroles and hot springs are found on the island (the most recent of these formed in 1953 and remains active), and seismic swarms have occurred on several occasions during the 20th century.