This book deals with the theoretical and the computational aspects of some of the variants of the classical Tower of Hanoi Problem (THP). • Chapter 5 considers the three-in-a-row puzzle with n ( ≥ 1) discs and 3 pegs, where the movements of the discs are allowed between adjacent pegs only • Chapter 6 treats the cyclic THP with n discs and 3 pegs arranged in a circle, and the disc movements are allowed in the clockwise / counterclockwise direction • Chapter 7 deals with the variant with parallel moves, which allows four types of moves - exchange as well as the single, consecutive and circular moves • Chapter 8 studies the THP with cyclic parallel moves • Chapter 9 gives the bottleneck generalization where the movements of the discs are restricted by the bottleneck size • Some four-peg variants are given in Chapter 10 • The final Chapter 11 gives some open problems