Countryside rhymes with:
cityside, sunnyside, alcide, backside, bayside, beachside, bedside, blindside, broadside, brookside, burnside, cambridgeside, cityside, curbside, dioxide, dockside, downside, exide, fireside, fratricide, fungicide, garside, gartside, genocide, germicide, glucoside, glycoside, graveside, harborside, herbicide, hillside, homicide, infanticide, insecticide, ironside, ketcherside, lakeside, mountainside, oceanside, oxide, parkside, peroxide, pesticide, poolside, prophesied, ringside, riverside, roadside, seaside, silverside, southside, suicide, sunnyside, superoxide, underside, wayside, whiteside, woodside
Countryside sounds like:
centrist, centrust, contract, contracted, contrast, contrasted, counteract, counteracted, countersued, countersuit, counterweight