The number of Bulgarians visiting Greece on holiday rose by an annual 60% in December to nearly 25,000, official statistics showed.
In December 2010, Bulgarian holidaymakers in Greece totalled 15,700, Bulgaria's National Statistics Institute reported.
At the same time, the number of Greeks visiting Bulgaria on holiday fell by 8.4% on the year to 25,100 in the last month of 2011.
A total of 75,000 Bulgarians travelled abroad on a holiday in December, down by 16% from the same period in the previous year.
Foreign tourist arrivals in Bulgaria increased by 4.8% on the year to 392,323 in December with tourist arrivals from EU member states edging up by 0.2% to 219,007 and those from other European countries rising by 11.4% to 142,859.
About 37% of all foreign tourists who visited Bulgaria in December were holidaymakers, 48% were transiting the country and 15% came on business.