ACE Study Tours © 01223/835055, www.study-tours.org. Two-week study tours of monasteries (Zemen, Rila. Rozhen. Bachkovo) and National Revival architecture in historic towns Melnik, Plovdiv, Veliko Tarnovo, Arbanassi and Koprivshtitsa), for £1135.

Avian Adventures 01384/372013, www.avianadventures.co.uk. Eight-day birdwatching tour of the Black Sea coast and Danube wetlands, tor £990.

Balkan Holidays 020/7543 5591; independent travel 020/7543 5569, www.balkanholidays.co.uk. Wide range of beach, skiing and mountain and lake holidays (from £255); multi-country tours (Bulgaria with Romania or Turkey); plus flight-only deals and special-interest tours tor Independent travellers.

Balkania Travel 7538 8654, ®avgarski@aol.com. Wine tours of Bulgaria for small groups (4 nights from £390.7 nights from £690).

Birdwatching Breaks 01227/740799, www.birdwatchingbreaks.com. Similar to Avian Adventures' package, for £995.

British-Bulgarian Friendship Society 28 Hagwood SI, London E3 3RU 020/7237 7616, www.bbfs.org.uk, kayannie@aol.com. Membership (£10 a year) gives access to cut-price natural history, wildlife, ornithology and textile tours, as well as lectures and social events.

Crystal Holidays 0870/848 7000, www.crystalski.co.uk. Ski packages to Borovets and Pamporovo, from £309 for seven nights.

Exodus 020/8675 5550, www.exodus.co.uk. Worldwide adventure specialists offering a fifteen-day Mountains and Monasteries tour (£765-775), one (£579-595) or two (£729) weeks' hiking in me Rhodopes over summer, and eight days' snowshoeing in the Rila Mountains in February (from £639).

First Choice 0870/754 3477, www.fcski.co.uk. Ski packages to Borovets and Pamporovo, from £319-555 for seven nights.

Inghams 020/8780 4444, www.inghams.com. Ski packages to Borovets (from £228 tor 7 nights), and a ten-day Bulgaria Discovery Tour (£518) in the summer.

Interchange 020/8681 3612, www.interchange.uk.com. Can arrange full-board homestays in Sofia (from £32 per person per night). tailormade itineraries, and hiking. Also flights to Sofia from London (from £239), and from Manchester via Frankfurt (from £309).

Limosa Holidays 01263/578143, limosaholidays@compuserve.com. Offers an eleven-day birdwatching lour in May (£1195) featuring the Rhodopes. Black Sea coast and Danube wetlands.

Naturetrek 01962/733051, www.naturetrek.co.uk. Covers the same ground as Limosa. but its spring tour focuses on flowers and butterflies as well, and it also does an autumn tour; each costs £995.

Neilson 0870/333 3356 www.neilson.co.uk. Ski packages to Borovets and Pamporovo, from £209 for seven nights.

Ornitholidays 01794/519445, www.ornittiolidays.co.uk. Eight days' birdwatching in the autumn, for £1099.

Silk Road Travel in Dublin 01/677 1029. Irish agents for Exodus.

Worldwide Adventures Abroad 0114/247 3400, www.adventures-abroad.com. Ten-day discovery lour with a little hiking, featuring Sofia, Plovdiv, Troyan, Rila, Veliko Tarnovo, Arbanassi and Shipka. for £943.