The Isaac Newton Group of Telescopes (ING) operates three telescopes: the 4.2 m William Herschel Telescope, the 2.5 m Isaac Newton Telescope and the 1 m Jacobus Kapteyn Telescope.

The 2.5 m Nordic Optical Telescope (NOT).
The 1 m Swedish Solar Telescope (SST) operated by the Institute for Solar Physics.
The 0.45 m Dutch Open Telescope (DOT).
A 0.6 m optical telescope.
The Carlsberg Meridian Telescope (CMT).
The 1.2 m Mercator Telescope.
The 2 m Liverpool Telescope.
The 10.4 m Gran Telescopio Canarias (under construction).
The 3.6 m Telescopio Nazionale Galileo (TNG).
The 17 m MAGIC Telescope, an air shower Cherenkov telescope for observing high energy gamma rays
The DOT and the SVST have been specifically built to study the Sun.