The simplest way to get to the Kremlin is to take the metro. From Smolenskaya on the pale-blue line (the metro station closest to the Lotte Hotel), travel two stops east to Aleksandrovskiy Sad. The exit from the station is right opposite the main Kremlin visitor entrance in the Kutafya Tower. The Lotte Hotel is also within reasonably comfortable walking distance of the Kremlin (around 25 minutes).