The telescope was erected in the Treptower Park and sheltered in a wooden building that also provided exhibition space and a lecture theatre.

The telescope has an aperture of 68 cm (27 in) and a focal length of 21 m (69 ft); the movable mass is 130 metric tons.

During World War II a bomb hit the southwest wing, but the Great Refractor was not severely damaged.

Friedrich Archenhold's first research, for which he was commissioned by Wilhelm Foerster, was aimed at developing the photographic method.

After building the giant telescope, he continued his technical tests (with photographs and moving images) and astronomical observations in his new "Treptow-Observatory".

Research reports and technical articles were published on the comets Perrine in 1897[4] and Halley in 1910,[5] a fireball[6] and noctilucent clouds.

[12] The cause of novae (surface eruptions on white dwarfs in cataclysmic variable stars) was still not understood at the time.

[14] The son of the observatory's founder, Günter Archenhold, published mainly on solar research[15][16][17][18] and the halo phenomenon.

A lecture theatre was also added, and in 1966 the "solar physics cabinet" (a special invention for showing the sun and its spectrum in a lecture hall) was created, which could project the Sun at 80 cm (31 in) diameter or a solar spectrum at 1.5 m length.

It was an invention by the brilliant optical engineer Edwin Rolf (Rathenow near Berlin), a further development of the Jensch coelostat for didactic (display) purposes.

The technical director, Eckehard Rothenberg was in charge for all further modernisations, the construction of two planetariums and the restoration of the Great Refractor.

In March 1982, the small planetarium in Treptow was replaced with a modern ZKP II model of the Zeiss company.

In 2007, the two houses became separate departments within the German Museum of Technology but were reunified in 2013, and form a single entity with the major planetarium and observatory in former West-Berlin since 2016.

In 1972, a research department for the history of astronomy was set up at the observatory, which was enriched by members of its own working group of hobby astronomers.

Didactical works, textbooks on the subject of astronomy and astronomy-related chapters in textbooks for various natural sciences were written by Director Herrmann and his staff, led by the qualified astronomy teachers Dietmar Fürst and Oliver Schwarz (the latter later received a professorship for physics didactics at the University of Siegen and headed the working group "Astronomiedidaktik" working group / education committee of the German Astronomical Society).

The editor and author was 1972 to 2014 Eckehard Rothenberg; since 2014 other members of the local hobby astronomers' club continue his work.

As a support association, the astronomers's club also relaunched and continued the Archenhold Observatory publication series after German reunification.

It had to be discontinued at the beginning of the 1990s because the research department(s) was dissolved, but was re-initiated in 2000 with a popular scientific-historical work by astronomer Susanne M Hoffmann.

With an aperture of 68 cm (27 in), a focal length of 21 m (69 ft) and a movable mass of 130 metric tons, it is considered a masterpiece of technology.