The mountain gorillas are found in Uganda, Rwanda & DRC Congo and each country has got the families which promotes gorilla trekking tours to several tourists visiting the 3 gorilla parks (Virunga, Volcanoes, Mgahinga & Bwindi impenetrable national park.
For travelers on limited time frame work can visit Rwanda which offers short day excursions from 1 – 3 days gorilla trek in the Volcanoes National Park.
The gorilla permits in Rwanda are so high compared to the other 2 countries (DRC Congo and Uganda where permits cost $ 400 and $ 600 USD per person respectively.
In Rwanda permit cost $ 750 USD but yo find that the safaris in Rwanda tend to be some how cheap compared to the other countries. If you are interested in a 1 Day gorilla trek in Rwanda book and it starts from 1150 USD per person