Dreaming about visiting a two-story mansion and swimming in a pool that resembles a small lake can be interpreted in several ways. Here are some insights:

1. Exploration of Emotions: Water in dreams often symbolizes emotions and the subconscious. Swimming in a pool that feels like a lake suggests you may be exploring deep or expansive feelings, perhaps related to the people in your life or your personal relationships.
2. Desire for Freedom: A large pool can represent a desire for freedom and escape. It may indicate a longing for relaxation and enjoyment, especially if the setting feels luxurious and inviting.
3. Social Connections: Visiting someone’s house signifies social interactions and relationships. This dream could reflect your feelings about your current social life, friendships, or family dynamics.
4. Personal Growth: The two-story aspect of the mansion may symbolize levels of consciousness or maturity. You might be on a journey of personal growth, exploring both your deeper self and your more superficial desires.
5. Adventure and New Experiences: The act of swimming can also symbolize adventure and the willingness to embrace new experiences. This dream might suggest that you are ready to dive into new opportunities in your life.

Consider how these themes relate to your current life situation. Reflecting on your feelings during the dream and any recent events in your waking life can provide additional clarity.