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Historically, FU Orionis-type stars are low-mass, pre-main sequence stars.The members of this class experience powerful accretion outbursts and remain inan enhanced accretion state for decades or centuries. V1515 Cyg, a classicalFUor, started brightening in the 1940s and reached its peak brightness in thelate 1970s. Following a sudden decrease in brightness it stayed in a minimumstate for a few months, then started a brightening for several years. Wepresent results of our ground-based photometric monitoring complemented withoptical/NIR spectroscopic monitoring. Our light curves show a long-term fadingwith strong variability on weekly and monthly time scales. The optical spectrashow P Cygni profiles and broad blue-shifted absorption lines, commonproperties of FUors. However, V1515 Cyg lacks the P Cygni profile in the Ca II8498 \r{A} line, a part of the Ca infrared triplet (IRT), formed by anoutflowing wind, suggesting that the absorbing gas in the wind is opticallythin. The newly obtained near-infrared spectrum shows the strengthening of theCO bandhead and the FeH molecular band, indicating that the disk has becomecooler since the last spectroscopic observation in 2015. The current luminosityof the accretion disk dropped from the peak value of 138 $L_{\odot}$ to about45 $L_{\odot}$, suggesting that the long-term fading is also partly caused bythe dropping of the accretion rate.

A multi-epoch, multi-wavelength study of the classical FUor V1515 Cyg approaching quiescence