Complex sentence: The area has no defined boundaries and straddles the convergence of five London boroughs and three postal districts, although an electoral ward named Crystal Palace and Crystal Palace Park are entirely contained within the London Borough of Bromley.
Split into simpler sentences: The area has no defined boundaries and straddles the convergence of five London boroughs and three postal districts. However, an electoral ward named Crystal Palace and Crystal Palace Park are entirely contained within the London Borough of Bromley.