European Court of Human Rights
The court was open for signature on Nov 4 1950, but did not begin operating until Sept 3 1953. The purpose is to hold states accountable for the human rights set out in the Universal Declaration of Human Rights as well as rights added by protocols. Either other states or individuals can appeal to the court against a state. Judges of the court are elected for nonrenewable 9 year terms. States propose lists of 3 candidates and the winner is elected through the Parliamentary Assembly of the Council of Europe.
The official website is http://www.echr.coe.int/ECHR/homepage_en, but I would suggest the FAQ page (http://www.echr.coe.int/NR/rdonlyres/5C53ADA4-80F8-42CB-B8BD-CBBB781F42C8/0/FAQ_ENG_A4.pdf) to get a good overview of the system.