What type of estate represents the most extensive interest in land that can be enjoyed and is of perpetual duration?

A fee simple estate represents the most extensive interest in land that can be enjoyed, as it offers complete ownership of the property and is of perpetual duration. This type of estate allows the owner to use, sell, lease, or give away the property without any limitations, subject only to governmental powers such as taxation or eminent domain. It is the highest form of estate in real property and continues indefinitely, meaning it does not end upon the owner's death and can be inherited.

In contrast, a life estate is limited to the duration of a person's life, terminating when that person passes away. A conditional estate is subject to specific conditions that could lead to the termination of the estate if those conditions are violated. Tenancy in common involves shared ownership of a property among multiple parties, where each party has an undivided interest in the whole property without any right of survivorship. Unlike the fee simple estate, these other types of estates come with certain limitations and conditions that restrict the owner's rights.