The national calendar of Bangladesh follows the Bengali calendar alongside the Gregorian system and the Islamic lunar calendar. The Bengali calendar was reformed in 1966 under Bangla Academy direction to align agricultural festivals with solar positioning. The year 1431 in Bengali calendar corresponds to 2024 CE. This triple-calendar system creates a festival density unmatched in South Asia, with religious holidays shifting annually by lunar calculation while seasonal festivals anchor to fixed solar dates.
Pohela Boishakh falls on April 14 each year, marking the Bengali New Year and the single largest secular gathering in Bangladesh. The celebration centers on Dhaka University campus and Ramna Batamul area, where the cultural organization Chhayanaut has conducted sunrise musical performances since 1967. Attendance at Ramna Batamul exceeds 100,000 participants by 6:00 AM. The tradition began as a merchant practice in Mughal Bengal when Emperor Akbar reformed the tax calendar in 1556, requiring rent collection to align with harvest seasons rather than lunar months. Modern Pohela Boishakh observance includes wearing red-and-white traditional dress, consuming panta bhat with fried hilsa fish, and painting alpana geometric designs on thresholds. Street processions called Mongol Shobhajatra, organized by Dhaka University Faculty of Fine Arts since 1989, feature papier-mâché effigies of animals and mythological figures, drawing crowds exceeding one million along a three-kilometer route. The procession was inscribed on UNESCO Intangible Cultural Heritage list in 2016. Business ledgers are traditionally closed on Chaitra 30 and reopened on Boishakh 1, with new account books consecrated at Dhakeshwari Temple and other commercial centers. Rural fairs called Boishakhi Mela operate across Bangladesh during the first week of Boishakh, with the Jessore fair documented continuously since 1788.
Ekushey February commemorates the Bengali language movement martyrs killed on February 21, 1952, when police fired on students protesting Urdu-only language policies in Dhaka. Five confirmed deaths occurred that day: Abul Barkat, Abdul Jabbar, Rafiq Uddin Ahmed, Abdus Salam, and Shafiur Rahman. The Shaheed Minar monument was first constructed in bamboo and canvas on February 23, 1952, destroyed by police on February 26, rebuilt in concrete in 1963. The current structure stands 14 meters tall with five pillars representing the martyrs. Observance begins at midnight on February 20 with barefoot processions to the monument, participants carrying flower wreaths and singing "Amar Bhaiyer Rokte Rangano Ekushey February," composed by Abdul Gaffar Choudhury with music by Altaf Mahmud in 1953. The month-long Ekushey Book Fair, organized by Bangla Academy since 1972, operates on Bangla Academy grounds and Suhrawardy Udyan, hosting 550 publisher stalls in 2024. Daily attendance during the fair's final week exceeds 200,000. UNESCO declared February 21 as International Mother Language Day in 1999, extending the commemoration beyond Bangladesh.
Durga Puja represents the largest Hindu festival in Bangladesh, occurring over five days in September or October depending on lunar calendar calculations. The festival honors the goddess Durga's victory over the demon Mahishasura, with celebrations concentrated in September-October period called Sharad or autumn season. Dhakeshwari Temple in Dhaka has conducted continuous Durga Puja since its establishment in the 12th century. The 2023 festival involved approximately 32,000 puja mandaps nationwide according to Bangladesh Puja Celebration Council estimates. Major pandals in Dhaka include Ramkrishna Mission, Dhakeshwari National Temple, and Ramna Kali Mandir. Kumari Puja, the worship of pre-pubescent girls as embodiments of the goddess, occurs on the eighth day at select temples including Kantajew Temple in Dinajpur. Durga Puja in Bangladesh retains practices discontinued in West Bengal, including the immersion of clay idols in natural water bodies rather than artificial tanks. The Chittagong Hill Tracts Buddhist and indigenous communities observe the same October period with different festivals, creating regional variation in holiday density. Post-independence Bangladesh has seen Durga Puja evolve from neighborhood celebrations to elaborate themed pandals, with Dhaka University area pandals attracting Hindu and Muslim visitors in roughly equal numbers based on 2019 survey data from Dhaka University Sociology Department.
Eid-ul-Fitr concludes Ramadan fasting, falling on the first day of Shawwal in the Islamic calendar. The date shifts approximately 10 days earlier each Gregorian year due to the 354-day lunar calendar. Bangladesh's National Moon Sighting Committee, established under the Islamic Foundation Bangladesh, meets at Baitul Mukarram Mosque to declare Eid based on crescent moon observation. The 2024 Eid-ul-Fitr occurred on April 11. Morning prayers begin between 7:00 and 8:00 AM at mosques, open grounds, and eidgahs across Bangladesh. Dhaka's largest Eid congregation occurs at the National Eidgah Maidan in central Dhaka, with capacity for 300,000 worshippers. The three-day public holiday generates the largest internal migration in Bangladesh, with Dhaka's population decreasing by an estimated 40 percent as residents return to ancestral villages. Kamalapur Railway Station and Sadarghat Launch Terminal handle over 500,000 departures in the 48 hours preceding Eid based on Bangladesh Railway and Bangladesh Inland Water Transport Authority 2023 figures. Traditional Eid food preparation centers on beef and mutton dishes, particularly kacchi biryani prepared in dum style with rice and meat layered in sealed clay pots. Semai, a vermicelli dessert cooked in milk and sugar, appears at every Eid meal. Zakat-ul-Fitr, a mandatory charity of approximately 2 kilograms of rice or equivalent cash per household member, is distributed to the poor before Eid prayers. Children receive salami or cash gifts from elders, with typical amounts ranging from 50 to 500 taka depending on family means.
Eid-ul-Adha falls on the 10th of Dhul Hijjah, approximately 70 days after Eid-ul-Fitr. The festival commemorates Abraham's willingness to sacrifice his son, with animal sacrifice as the central ritual. Bangladesh sacrifices an estimated 10 million animals during the three-day festival according to 2023 Department of Livestock Services data: approximately 6 million cattle, 3 million goats, and 1 million sheep. Islamic law requires the animal to be healthy and above minimum age: one year for goats and sheep, two years for cattle. Sacrifice rules divide the meat into three portions: one-third for the family, one-third for relatives, and one-third for the poor. Dhaka City Corporation designates approximately 1,000 sacrifice spots annually to manage waste disposal. The 2023 Eid-ul-Adha generated an estimated 50,000 tons of animal waste in Dhaka alone, removed by 12,000 sanitation workers over 72 hours. Cattle markets called haat operate for two weeks before Eid-ul-Adha, with major markets at Gabtoli in Dhaka and Ershad Market in Chittagong. A premium cattle can sell for 500,000 taka, though average prices range from 50,000 to 150,000 taka. The practice of urban families conducting sacrifices in apartment complexes or narrow streets has created ongoing debate about hygiene and animal welfare. Bangladesh Animal Welfare Foundation documented 2,000 animal cruelty complaints during 2023 Eid-ul-Adha, primarily related to improper slaughter technique or transport conditions.