Silverback size: A full-grown silverback stands at just over six feet tall.
Weight: 135-190kg
Life expectancy: 52 years
Habitat: Dense forest along the Virunga Volcanoes that run through a western section of the Rift Valley in East Africa which takes in parts of Uganda, Rwanda and the Democratic Republic of Congo.
Diet: Vegetarian
Population: There are roughly 700 mountain gorillas left in the wild.
Travel facts: For the most direct route to Entebbe, Uganda, book online with KLM which flies out of Amsterdam. See www.klm.com for prices. For return flights to Amsterdam go to www.aerlingus.com.
Trekking: A three-day trekking package with Pearlafric Travel Bureau Ltd costs €590 and includes overland travel, accommodation for two nights including a second night stay at Lake Bunyonyi, all meals and one gorilla permit. For more information go to www.pearlafric.com.
Medical: A reasonable degree of fitness is required for the trek and no one under 15 is allowed to take part. It is necessary to be vaccinated against yellow fever to enter Uganda. Other recommended vaccinations include polio, tetanus, and hepatitis A & B. Malaria prophylactics are also recommended.
For more information go to www.tmb.ie.
Visas: Irish citizens do not require a visa for Uganda.