The Araucaria Project, started in 2000, is a collaboration between astronomers from institutions in Chile, the US and Europe.
Its principal aim is to provide an improved calibration of the local extragalactic distance scale.
In the process of setting up the extragalactic distance scale, the greatest difficulty leading to the currently largest contribution on the systematic uncertainty of the Hubble constant lies in the determination of accurate absolute distances to nearby galaxies.
The principal reason for this persisting difficulty is in the ill-known dependences of stellar standard candles, used to measure the distances of nearby galaxies, on the environmental properties of their host galaxies (metallicity, age of the stellar populations).
The Araucaria Project is an effort to remedy this situation for several of the most important stellar candles, including Cepheid variables, RR Lyrae stars, red clump giants, and blue supergiants which all have the potential to provide accurate distance determinations to nearby galaxies once their environmental dependences are well calibrated.