According to the CTA Declaration of Intent, three major reviews are the basis for CTA Construction approval:

• The Science Performance and Preliminary Requirement Review (SPPRR)
• The Preliminary Design Review (PDR)
• The Critical Design Review (CDR)

The reviews are conducted by the Resource Board-appointed Scientific and Technical Advisory Committee (STAC), which monitors and evaluates the scientific goals and assesses the overall model for CTA, including its technical design. The SPPRR was successfully completed in February 2013 and the PDR was concluded in November 2013, on the basis of the Preliminary Technical Design Report.

Project Scope

A high-level work breakdown structure is illustrated in the below figure. The diagram covers all phases of the project (see project timeline below), but some activities (e.g. site negotiations) are only relevant to particular phases.

Construction Project Timeline

The build-up to construction continues in 2016 with first telescopes on site expected in early 2017. In the mean time, we'll be finalizing site negotiations, our finances and preparing the sites for construction. The timeline below illustrates the three major project phases, our progress along the pre-construction phase timeline and tentative future schedule.


Site Selection


On 15 and 16 July 2015, the Cherenkov Telescope Array (CTA) Resource Board decided to enter into detailed contract negotiations for hosting CTA on the European Southern Observatory (ESO) Paranal grounds in Chile and at the Instituto de Astrofisica de Canarias (IAC), Roque de los Muchachos Observatory in La Palma, Spain.

The Board, composed of representatives of ministries and funding agencies from Austria, Brazil, the Czech Republic, France, Germany, Italy, Namibia, the Netherlands, Japan, Poland, South Africa, Spain, Switzerland and the UK, decided after months of negotiations and careful consideration of extensive studies of the environmental conditions, simulations of the science performance and assessments of construction and operation costs to start contract negotiations with ESO and Spain. The Namibian and Mexican sites will be kept as viable alternatives.

The southern site is less than 10 km southeast of ESO’s existing Paranal Observatory in the Atacama Desert, which is considered one of the driest and most isolated regions on earth – an astronomical paradise.

The northern site is located on the existing site of the Instituto Astrofisica de Canarias Observatorio del Roque de los Muchachos on the island of La Palma, the fifth largest island in the Canary Islands.

Read the offical press release.








Project Management

The Project Office, located in Heidelberg, Germany, is responsible for the functions of general project management, technical coordination and system integration for CTA. To contact the Project Office, email Tiziana Abegg (Office Manager) or Megan Grunewald​ (Communications Officer).

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