In cities split between Brazil and Uruguay like Chuí/Chuy and Santana do Livramento/Rivera you can cross the national border just by walking across the street. What happens if the police sees a
BRAZIL–URUGUAY BORDER: All You Need to Know BEFORE You Go (with Photos)
Chuy Uruguay is a city of Uruguay that borders Brazil and has nice beaches
VIAGEM DE MOTO DE BH AO URUGUAI 01/2009 – EXPEDITION BRAZIL – URUGUAY FROM COAST TO COAST
A Night in “Fucking Chuí” Between Uruguay and Brazil
Uruguayan Odyssey — Dodgy Knees
Chuí - Wikipedia
Chuy – Travel guide at Wikivoyage
Visit El Chuy in a tailor-made tour