Note
4.24 miles walking from the hotel to Arbatskaya metro station and then from Ploschad Revolyutsil metro station to Red Square (& Lenin mausoleum), then onto GUM department store, before a visit to St. Basil's cathedral, then the Tretatykov Gallery & finally to the Cathedral of Christ the Saviour & back to the hotel.
N.B. distance doesn't include that inside the metro system or walking around the 2 cathedrals & the art gallery.
Back out in the evening to a restaurant (Cafe My My) on Old Arbat Street and then back via New Arbat Street (2.59 miles).
Total distance: 6.83 miles