One of the novels the much-missed Dave Duncan wrote before he hied himself off to the great Unknown was Pillar of Darkness. 

Two hundred miles wide and higher than the moon, Sungoback has stood over central Africa for thirty years, a pillar of light by night and of darkness by day. Science cannot explain it; it destroys technology. What secret lies at its centre: aliens, eternal life, distant past, or far future? Most who venture inside Sungoback are never seen again. Why would anybody dare?

They all have their reasons. Pillar of Darkness tells of a party of nine very dissimilar people, who venture into Sungoback together, bound by their motives, their sufferings, and—eventually—their fates.

Pillar of Darkness is now available in trade paperback and ebook from Five Rivers, and your favourite online bookseller worldwide.

Dave Duncan may be gone, but his legacy lives on.