MADLab Phase Four: CITY IN THE SKY, by Katherine Vondy

When Sage and her brother Rowan go hiking in 2024, they set out for the ruins of the White City, but a ghostly encounter with a couple that honeymooned there in 1899 shows that the past never completely disappears. As questions about inheritance and destiny reverberate around Echo Mountain, the siblings must decide whether the future is pre-determined or written in the stars.