It appears there is no widely recognized or verifiable town or city named “Salduś” in Poland for which specific travel data can be retrieved. A thorough search for “Salduś Poland” does not yield a significant or documented location.

As per your critical instruction: “Only use real, verifiable data. Never make up statistics, prices, or facts.”

Since “Salduś” does not appear to be a real, verifiable location, I cannot provide accurate or factual information regarding its weather, typical costs, crowd levels, events, or activities for March while adhering to your strict data requirements.

To provide a helpful response within your constraints, I would need a real, verifiable location in Poland. If “Salduś” was intended as a placeholder or a different location was meant, please provide the correct name of a verifiable Polish town or city, and I would be happy to generate a guide based on real data for that specific place.