Lake Chala, also known as Dschalla, is a crater lake in a caldera on the borders of Kenya and Tanzania on the eastern edge of Mount Kilimanjaro, 8km north of Taveta and 55 kms from the town of Moshi. Depending on the time of year, it ranges in colour from deep blue to turquoise and green, it is surrounded by a 100 metres high crater rim. The lake is fed by groundwater flows, which come from Mount Kilimanjaro, fed and drained under ground with a rate of about 10 million m³ / year. Even the Chalk loses volume. Its level had dropped in the last 6 years, by 2.4 metres, at the start of 2011 the water level has risen again by over 1 metre.