>>512477829
It depends on what timeframe you look. Pretty sure at some point between 1147 and 1240 Kiev was better fortified, but by the 14th century Moscow cucked the Lithuanians already who tried to siege kremlin walls 3 times.

Another thing I just recently learned that kremlin could be flooded from all sides like medieval castles with ditches. I've been quite a lot of times there but I never knew of underground river neglinnaya which was actual river in middle ages