Shakespeare's "Hamlet" is not only a hallmark of Elizabethan drama but a landmark of literary achievement renowned for its deep exploration of the human condition. Central to its enduring relevance is the masterful use of symbolism, which Shakespeare employs to enhance the play's thematic complexity and emotional depth. In "Hamlet," symbols are not mere literary devices but are intricately woven into the fabric of the narrative, serving as windows into the characters' minds and the play's broader philosophical inquiries. 

One of the most potent symbols in "Hamlet" is Yorick's skull, which Hamlet discovers in the graveyard. The skull, a stark reminder of the inevitability of death, symbolizes the ultimate futility of human endeavors and the transient nature of life. Hamlet's contemplation of the skull evokes profound reflections on mortality, identity, and the meaninglessness of earthly glory. It serves as a poignant memento mori, an artistic or symbolic reminder of the inevitability of death, which was a common theme in Elizabethan literature. 

The ghost of King Hamlet is another significant symbol in the play. It represents not only the literal presence of the dead king but also the lingering impact of past actions and unresolved issues. The ghost's appearance sets in motion the play's central conflict and propels Hamlet into his deep existential and moral dilemma. It symbolizes the weight of legacy, the inescapability of the past, and the murky boundary between the supernatural and the real. 

The play-within-a-play, "The Mousetrap," is a critical symbol that Hamlet uses to expose King Claudius's guilt. It represents the power of theater as a mirror of reality and a tool for unmasking truth. Shakespeare uses this meta-theatrical device to explore themes of appearance versus reality, illusion, and the artifice inherent in human behavior. 

Ophelia's flowers, each with its own symbolic meaning, represent the complex interplay of innocence, madness, and the societal constraints imposed on women. Her distribution of flowers in Act 4, Scene 5, is laden with symbolic significance, reflecting her descent into madness and the loss of innocence in the corrupt world of Elsinore. 

The symbol of the unweeded garden, which Hamlet refers to in his first soliloquy, reflects the moral and political decay of Denmark. The garden, overrun with weeds, symbolizes the natural order's disruption and the kingdom's descent into chaos and corruption under Claudius's rule. 

Additionally, Fortinbras's invasion of Denmark symbolizes the cycle of political ambition and the inevitable consequences of power struggles. It mirrors Hamlet's internal conflict and the broader theme of the succession and legitimacy of power. 

Furthermore, the motif of poison, both literal and metaphorical, permeates the play. Poison symbolizes betrayal, deceit, and the corrupting influence of sin. Claudius's act of poisoning King Hamlet becomes a metaphor for the moral contamination that afflicts the entire kingdom. 

In conclusion, the symbolism in "Hamlet" is multi-layered and integral to the play's exploration of themes such as life and death, action and inaction, reality and appearance, and the moral corruption of power. Shakespeare's use of these symbols allows for a richer understanding of the characters' psychological states and the play's underlying philosophical questions. They elevate "Hamlet" from a mere revenge tragedy to a profound meditation on the human experience, making it a timeless masterpiece that continues to resonate with modern audiences.