The barrio of Monserrat in Buenos Aires, despite being the one of the oldest, most historically interesting parts of the city, often plays second fiddle to San Telmo. Some Buenos Aires Real Estate agents will even try to tell you that property found in Monserrat is in fact in San Telmo. It is hard to understand this bias in favour of San Telmo, because Monserrat is a very attractive and interesting neighbourhood (not that San Telmo isn’t attractive too).
Based around Buenos Aires main square, Plaza de Mayo (near to where the city was officially first settled by the Spanish way back in 1580), Monserrat is a barrio full of history, atmosphere, wonderful architecture.