This paper addresses the grammar of PP-like free relatives (= PP-FRs) such as the locative clause in Bello schläft, wo Grace schläft ‘Bello is sleeping where Grace is sleeping’. The most prominent compositional analysis of PP-FRs is developed by Caponigro (2004), Caponigro and Pearl (2009), and Hall and Caponigro (2010). They derive PP-FRs from a stacked CP-structure that is based on silent prepositions and a nominal treatment of wh-words such as where. I first take issue with this analysis by means of a detailed discussion of subordinate clauses introduced by wo ‘where’ in German. Specifically, I show that wo-clauses do not involve silent prepositions, and that both wo and wo-clauses have a prepositional instead of a nominal nature. Second, I sketch a surface-oriented alternative approach to PP-FRs that dispenses with silent prepositions and assigns the prepositional nature of PP-like wh-words a key role in the derivation. Specifically, I propose that the fronting of PP-like wh-words in free relatives licenses an abstraction over predicates (instead of entities) and a corresponding type shifting. The new analysis is related to analyses of corresponding subordinate headed relative and interrogative clauses. Furthermore, it is confronted with potential general constraints on higher-order abstraction as argued for, in particular, by Poole (2017).